Indazole-carboxamide compounds as 5-HT4 receptor agonists

ABSTRACT

The invention provides novel indazole-carboxamide 5-HT 4  receptor agonist compounds. The invention also provides pharmaceutical compositions comprising such compounds, methods of using such compounds to treat diseases associated with 5-HT 4  receptor activity, and processes and intermediates useful for preparing such compounds.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.60/545,702, filed on Feb. 18, 2004, the disclosure of which isincorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention is directed to indazole-carboxamide compounds which areuseful as 5-HT₄ receptor agonists. The invention is also directed topharmaceutical compositions comprising such compounds, methods of usingsuch compounds for treating medical conditions mediated by 5-HT₄receptor activity, and processes and intermediates useful for preparingsuch compounds.

2. State of the Art

Serotonin (5-hydroxytryptamine, 5-HT) is a neurotransmitter that iswidely distributed throughout the body, both in the central nervoussystem and in peripheral systems. At least seven subtypes of serotoninreceptors have been identified and the interaction of serotonin withthese different receptors is linked to a wide variety of physiologicalfunctions. There has been, therefore, substantial interest in developingtherapeutic agents that target specific 5-HT receptor subtypes.

In particular, characterization of 5-HT₄ receptors and identification ofpharmaceutical agents that interact with them has been the focus ofsignificant recent activity. (See, for example, the review by Langloisand Fischmeister, J. Med. Chem. 2003, 46, 319-344.) 5-HT₄ receptoragonists are useful for the treatment of disorders of reduced motilityof the gastrointestinal tract. Such disorders include irritable bowelsyndrome (IBS), chronic constipation, functional dyspepsia, delayedgastric emptying, gastroesophageal reflux disease (GERD), gastroparesis,post-operative ileus, intestinal pseudo-obstruction, and drug-induceddelayed transit. In addition, it has been suggested that some 5-HT₄receptor agonist compounds may be used in the treatment of centralnervous system disorders including cognitive disorders, behavioraldisorders, mood disorders, and disorders of control of autonomicfunction.

Despite the broad utility of pharmaceutical agents modulating 5-HT₄receptor activity, few 5-HT₄ receptor agonist compounds are in clinicaluse at present. One agent, cisapride, that was utilized extensively fortreatment of motility disorders of the gastrointestinal tract waswithdrawn from the market, reportedly due to cardiac side effects. Latestage clinical trials of another agent, prucalopride, have beensuspended.

Accordingly, there is a need for new 5-HT₄ receptor agonists thatachieve their desired effects with minimal side effects. Preferredagents may possess, among other properties, improved selectivity,potency, pharmacokinetic properties, and/or duration of action.

SUMMARY OF THE INVENTION

The invention provides novel compounds that possess 5-HT₄ receptoragonist activity. Among other properties, compounds of the inventionhave been found to be potent and selective 5-HT₄ receptor agonists. Inaddition, compounds of the invention have been found to exhibitfavorable pharmacokinetic properties which are predictive of goodbioavailability upon oral administration.

Accordingly, the invention provides a compound of formula (I):

wherein:

-   -   R¹ is hydrogen, halo, hydroxy, C₁₋₄alkyl, or C₁₋₄alkoxy;    -   R² is C₃₋₄alkyl, or C₃₋₆cycloalkyl; and    -   W is selected from:        -   (i) a group of formula (II):        -   wherein X is:            -   NC(O)R^(a), wherein R^(a) is C₁₋₃alkyl or                tetrahydrofuranyl, wherein C₁₋₃ alkyl is optionally                substituted with —OH or C₁₋₃alkoxy;            -   S(O)₂; or            -   NS(O)₂R^(b), wherein R^(b) is methyl, optionally                substituted with —OH, C₁₋₃alkoxy, C₅₋₆cycloalkyl, or                —S(O)₂—C₁₋₃alkyl;        -   (ii) a group of formula (III):        -   wherein:            -   Ry is —OH or C₁₋₃alkoxy;            -   p is 0 or 1;            -   n is 1 or 2; and            -   Y is:                -   N(R^(c))C(O)R^(d), wherein R^(c) is hydrogen or                    C₁₋₃alkyl and R^(d) is C₁₋₃alkyl optionally                    substituted with —OH or C₁₋₃alkoxy, or                -   N(R^(e))S(O)₂R^(f), wherein R^(e) is hydrogen and                    R^(f is C) ₁₋₃alkyl, optionally substituted with                    —OH, C₁₋₃alkoxy, C₅₋₆cycloalkyl, or                    —S(O)₂—C₁₋₃alkyl; and        -   (iii) a group of formula (IV):        -   wherein:            -   R^(z) is hydrogen, C₁₋₃alkyl, or C₂₋₃alkyl substituted                with —OH or C₁₋₃alkoxy;            -   m is 1 or 2;            -   q is 1 or 2, provided that the sum of m and q is not                equal to 4; and            -   Z is:                -   N^(c)(O)R^(g), wherein R^(g) is C₁₋₃alkyl,                    optionally substituted with —OH or C₁₋₃alkoxy,                -   S(O)₂; or                -   NS(O)₂R^(h), wherein R^(h) is methyl, optionally                    substituted with —OH, C₁₋₃alkoxy, C₅₋₆cycloalkyl, or                    —S(O)₂—C₁₋₃alkyl;    -   or a pharmaceutically-acceptable salt or solvate or stereoisomer        thereof.

The invention also provides a pharmaceutical composition comprising acompound of the invention and a pharmaceutically-acceptable carrier.

The invention also provides a method of treating a disease or conditionassociated with 5-HT₄ receptor activity, e.g. a disorder of reducedmotility of the gastrointestinal tract, the method comprisingadministering to the mammal, a therapeutically effective amount of acompound of the invention.

Further, the invention provides a method of treating a disease orcondition associated with 5-HT₄ receptor activity in a mammal, themethod comprising administering to the mammal, a therapeuticallyeffective amount of a pharmaceutical composition of the invention.

The compounds of the invention can also be used as research tools, i.e.to study biological systems or samples, or for studying the activity ofother chemical compounds. Accordingly, in another of its method aspects,the invention provides a method of using a compound of formula (I), or apharmaceutically acceptable salt or solvate or stereoisomer thereof, asa research tool for studying a biological system or sample or fordiscovering new 5-HT₄ receptor agonists, the method comprisingcontacting a biological system or sample with a compound of theinvention and determining the effects caused by the compound on thebiological system or sample.

In separate and distinct aspects, the invention also provides syntheticprocesses and intermediates described herein, which are useful forpreparing compounds of the invention.

The invention also provides a compound of the invention as describedherein for use in medical therapy, as well as the use of a compound ofthe invention in the manufacture of a formulation or medicament fortreating a disease or condition associated with 5-HT₄ receptor activity,e.g. a disorder of reduced motility of the gastrointestinal tract, in amammal.

DETAILED DESCRIPTION OF THE INVENTION

The invention provides novel indazole-carboxamide 5-HT₄ receptoragonists of formula (I), or pharmaceutically-acceptable salts orsolvates or stereoisomers thereof. The following substituents and valuesare intended to provide representative examples of various aspects ofthis invention. These representative values are intended to furtherdefine such aspects and are not intended to exclude other values orlimit the scope of the invention.

In a specific aspect of the invention, R¹ is hydrogen, halo, C₁₋₄alkyl,or C₁₋₄alkoxy.

In other specific aspects, R¹ is hydrogen, halo, or C₁₋₄alkyl; or R¹ ishydrogen or halo; or R¹ is fluoro.

In yet another specific aspect, R¹ is hydrogen.

In a specific aspect, R² is C₃₋₄alkyl or C₃₋₆cycloalkyl.

In another specific aspect, R² is C₃₋₄alkyl. Representative R² groupsinclude n-propyl, isopropyl, n-butyl, sec-butyl, and tert-butyl.

In another specific aspect, R² is isopropyl.

In yet another specific aspect R² is cyclobutyl or cyclopentyl.

In a specific aspect, W is a group of formula (II) wherein all of thevariables are defined as in formula (II).

In another specific aspect, W is a group of formula (II), wherein R^(a)is C₁₋₃alkyl and R^(b) is methyl.

In another specific aspect, W is a group of formula (II), wherein X isNC(O)R^(a) wherein R^(a) is defined as in formula (II). In otherspecific aspects, W is a group of formula (II), wherein X is NC(O)R^(a),wherein R^(a) is C₁₋₃alkyl, specifically methyl, ethyl, n-propyl, orisopropyl, or tetrahydrofuran-2-yl or tetrahydrofuran-3-yl; or R^(a) isC₁₋₃alkyl.

In yet another specific aspect, W is a group of formula (II), wherein Xis NC(O)CH₃, which forms W having the value 4-acetyl-piperazin-1-yl.

In another specific aspect, W is a group of formula (II), wherein X isS(O)₂.

In another specific aspect, W is a group of formula (II), wherein X isNS(O)₂R^(b), wherein R^(b) is defined as in formula (II). In anotherspecific aspect, W is a group of formula (II), wherein X is NS(O)₂R^(b),wherein R^(b) is CH₃ optionally substituted with C₅₋₆cycloalkyl or with—S(O)₂—C₁₋₃alkyl. Representative R^(b) values within this aspect includemethyl, —CH₂cyclopentyl, —CH₂cyclohexyl, —CH₂SO₂CH₃, and —CH₂SO₂C₂H₅.

In yet another specific aspect, W is a group of formula (II) wherein Xis NS(O)₂CH₃, which forms W having the value4-methanesulfonyl-piperazin-1-yl.

In another specific aspect, W is a group of formula (III) wherein R^(y)is —OH.

In another specific aspect, W is a group of formula (III) wherein R^(y)is C₁₋₃alkoxy, for example R^(y) is —OCH₃, —OC₂H₅, or —OC₃H₇.

In other specific aspects W is a group of formula (III) wherein p is 0,or wherein p is 1.

In other specific aspects W is a group of formula (III) wherein n is 1,i.e. W is an optionally substituted pyrrolidinyl ring; or wherein n is2, i.e. W is an optionally substituted piperidinyl ring.

In another specific aspect, W is a group of formula (III) wherein Y isN(R^(c))C(O)R^(d) wherein R^(c) and R^(d) are defined as in formula(III). In other specific aspects, W is a group of formula (III) whereinY is N(R^(c))C(O)R^(d) wherein R^(c) is hydrogen; and wherein R^(c) isC₁₋₃alkyl.

In another specific aspect, W is a group of formula (III) wherein Y isN(R^(c))C(O)R^(d) wherein R^(d) is C₁₋₃alkyl optionally substituted with—OH or C₁₋₃alkoxy. Representative values of R^(d) within this aspectinclude methyl, ethyl, —CH₂OH, and —CH(OH)CH₃.

In another specific aspect, W is a group of formula (II) wherein Y isNCH₃C(O)CH₃.

In yet another specific aspect, W is a group of formula (III) wherein Yis NHC(O)CH₃.

In another specific aspect, W is a group of formula (III) wherein Y isN(R^(e))S(O)₂R^(f) wherein R^(e) and R^(f) are defined as in formula(III). In another specific aspect, W is a group of formula (III) whereinY is N(R^(e))S(O)₂R^(f) wherein R^(f) is C₁₋₃alkyl optionallysubstituted with C₅₋₆cycloalkyl or with —S(O)₂—C₁₋₃alkyl. Representativevalues of R^(f) within this aspect include methyl, —CH₂cyclopentyl,—CH₂cyclohexyl, —CH₂SO₂CH₃, and —CH₂SO₂C₂H₅.

In another specific aspect, compounds of formula (I) are compoundswherein W is a group of formula (III) wherein p is 0 and n is 1. In yetanother specific aspect, compounds of formula (I) are compounds whereinW is a group of formula (III) wherein p is 0, n is 1, and Y isN(R^(c))C(O)R^(d).

In another specific aspect, W is a group of formula (IV), wherein R^(z)is hydrogen.

In another specific aspect, W is a group of formula (IV), wherein R^(z)is C₁₋₃alkyl, for example methyl, ethyl, and the like. In anotherspecific aspect, W is a group of formula (IV), wherein R^(z) isC₂₋₃alkyl substituted with —OH or with C₁₋₃alkoxy, for example R^(z) ishydroxyethyl, methoxyethyl, and the like. In another specific aspect, Wis a group of formula (IV), wherein R^(z) is methyl.

In a specific aspect, W is a group of formula (IV) wherein m is 1.

In another specific aspect, W is a group of formula (IV) wherein m is 2.

In a specific aspect, W is a group of formula (IV) wherein q is 1.

In another specific aspect, W is a group of formula (IV) wherein q is 2.

In a specific aspect, W is a group of formula (IV) wherein Z isNC(O)R^(g) wherein R^(g) is defined as in formula (IV). In otherspecific aspects, W is a group of formula (IV) wherein Z is NC(O)R^(g)wherein, R^(g) is C₁₋₃alkyl, optionally substituted with —OH; or R^(g)is methyl.

In a specific aspect, W is a group of formula (IV) wherein Z is S(O)₂.

In a specific aspect, W is a group of formula (IV) wherein Z isNS(O)₂R^(h), wherein Rh is defined as in formula (IV). In other specificaspects, W is a group of formula (IV) wherein Z is NS(O)₂R^(h) whereinR^(h) is methyl optionally substituted with C₅₋₆cycloalkyl or with—S(O)₂—C₁₋₃alkyl. Representative values of R^(h) include methyl,—CH₂cyclopentyl, —CH₂cyclohexyl, —CH₂SO₂CH₃, and —CH₂SO₂C₂H₅. In yetanother other specific aspect, W is a group of formula (IV) wherein Z isNS(O)₂CH₃.

In another specific aspect, compounds of formula (I) are compoundswherein W is a group of formula (IV) wherein m is 1 and q is 1. In yetanother specific aspect, compounds of formula (I) are compounds whereinW is a group of formula (IV) wherein m is 1, q is 1, and R^(z) ismethyl.

In one aspect, the invention provides a compound of formula (I) whereinR¹ is hydrogen or halo; R² is isopropyl or C₄₋₅cycloalkyl; and W isdefined as in formula (I).

In another aspect, the invention provides a compound of formula (I)wherein:

-   -   R¹ is hydrogen or halo;    -   R² is C₃₋₄alkyl or C₄₋₅cycloalkyl; and    -   W is selected from:        -   (i) a group of formula (II) wherein X is NC(O)CH₃, S(O)₂, or            NS(O)₂CH₃;        -   (ii) a group of formula (III) wherein p is 0, n is 1, and Y            is NCH₃C(O)CH₃; and        -   (iii) a group of formula (IV) wherein R^(z) is methyl, m is            1, q is 1, and Z is NC(O)CH₃, S(O)₂, or NS(O)₂CH₃.

In another aspect, the invention provides a compound of formula (I)wherein R¹ is hydrogen or halo; R² is C₃₋₄alkyl or C₄₋₅cycloalkyl; and Wis a group of formula (II) wherein X is NC(O)CH₃; S(O)₂; or NS(O)₂CH₃.

In another aspect, the invention provides a compound of formula (I)which is a compound of formula (V):

wherein:

-   -   R¹, R², and X take any of the generic, specific, or exemplary        values described above.

In yet another aspect, the invention provides a group of compounds offormula (VI):

wherein R¹, R², and W take the values shown in Table I. TABLE I Exam-ple No. R¹ R² W 1 H i-Pr

2 H i-Pr

3 H i-Pr

4 H i-Pr

5 H i-Pr

6 H i-Pr

7 H i-Pr

8 H i-Pr

9 H i-Pr

10 H i-Pr

11 H i-Pr

12 H i-Pr

13 H i-Pr

14 H i-Pr

15 H i-Pr

16 H i-Pr

17 H i-Pr

18 H i-Pr

19 H i-Pr

20 H i-Pr

21 H i-Pr

22 H i-Pr

23 H i-Pr

24 H i-Pr

25 H i-Pr

26 H i-Pr

27 H i-Pr

28 H i-Pr

29 H i-Pr

30 H i-Pr

31 F i-Pr

32 H n-Pr

33 H n-Bu

34 H cyclo- butyl

35 H cyclo- pentyl

36 H i-Pr

37 H i-Pr

38 H i-Pr

39 H i-Pr

40 H i-Pr

The chemical naming conventions used herein are illustrated for thecompound of Example 1:

which is designated 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-acetyl-piperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide,according to the AutoNom software, provided by MDL Information Systems,GmbH (Frankfurt, Germany). The designation (1S,3R,5R) describes therelative orientation of the bonds associated with the bicyclic ringsystem that are depicted as solid and dashed wedges.

The compound is alternatively denoted asN-[(3-endo)-8-[2-(4-acetyl-piperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl]-1-(1-methylethyl)-1H-indazole-3-carboxamide. In all of thecompounds depicted in Table I above, the indazole carboxamide is endo tothe azabicyclooctyl group.

Particular mention may be made of the following compounds:

-   1-isopropyl-1H-indazole-3-carboxylic acid    {(1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;-   1-isopropyl-1H-indazole-3-carboxylic acid    {(1S,3R,5R)-8-[2-(1,1-dioxo-1λ⁶-thiomorpholin-4-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;-   1-isopropyl-1H-indazole-3-carboxylic acid    {(1S,3R,5R)-8-[2-(4-methanesulfonyl-piperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;-   1-isopropyl-1H-indazole-3-carboxylic acid    {(1S,3R,5R)-8-[2-(3-(acetyl-methyl-amino)pyrrolidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;-   1-isopropyl-1H-indazole-3-carboxylic acid    {(1S,3R,5R)-8-[2-((R)-3-(acetyl-methylamino)pyrrolidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;-   1-isopropyl-1H-indazole-3-carboxylic acid    {(1S,3R,5R)-8-[2-((S)-3-(acetyl-methylamino)pyrrolidin-1-yl)-ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;-   1-isopropyl-1H-indazole-3-carboxylic acid    {(1S,3R,5R)-8-[2-[(1-acetyl-pyrrolidin-3-yl)-methylamino]ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;-   1-isopropyl-1H-indazole-3-carboxylic acid    {(1S,3R,5R)-8-[2-[((R)-1-acetyl-pyrrolidin-3-yl)methylamino]ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;-   1-isopropyl-1H-indazole-3-carboxylic acid    {(1S,3R,5R)-8-[2-[((S)-1-acetyl-pyrrolidin-3-yl)methylamino]ethyl]-8-aza-bicyclo[3.2.1]oct-3-yl}amide;-   1-isopropyl-1H-indazole-3-carboxylic acid    ((1S,3R,5R)-8-{2-[(1-methanesulfonyl-pyrrolidin-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;-   1-isopropyl-1H-indazole-3-carboxylic acid    ((1S,3R,5R)-8-{2-[((R)-1-methanesulfonylpyrrolidin-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;-   1-isopropyl-1H-indazole-3-carboxylic acid    ((1S,3R,5R)-8-{2-[((S)-1-methanesulfonylpyrrolidin-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;-   1-isopropyl-1H-indazole-3-carboxylic acid    {(1S,3R,5R)-8-[2-((1,1-dioxo-tetrahydro-1λ⁶-thiophen-3-yl)methylamino)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;-   1-isopropyl-1H-indazole-3-carboxylic acid    {(1S,3R,5R)-8-[2-((R)-(1,1-dioxo-tetrahydro-1λ⁶-thiophen-3-yl)methylamino)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;    and-   1-isopropyl-1H-indazole-3-carboxylic acid    {(1S,3R,5R)-8-[2-((S)-(1,1-dioxo-tetrahydro-1λ⁶-thiophen-3-yl)methylamino)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;

As illustrated above, the compounds of the invention may contain achiral center. Accordingly, the invention includes racemic mixtures,pure stereoisomers, and stereoisomer-enriched mixtures of such isomers,unless otherwise indicated. When a particular stereoisomer is shown, itwill be understood by those skilled in the art, that minor amounts ofother stereoisomers may be present in the compositions of the inventionunless otherwise indicated, provided that the utility of the compositionas a whole is not eliminated by the presence of such other isomers.

Definitions

When describing the compounds, compositions and methods of theinvention, the following terms have the following meanings, unlessotherwise indicated.

The term “alkyl” means a monovalent saturated hydrocarbon group whichmay be linear or branched or combinations thereof. Unless otherwisedefined, such alkyl groups typically contain from 1 to 10 carbon atoms.Representative alkyl groups include, by way of example, methyl, ethyl,n-propyl (n-Pr), isopropyl (i-Pr), n-butyl (n-Bu), sec-butyl, isobutyl,tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl andthe like.

The term “alkoxy” means a monovalent group —O-alkyl, where alkyl isdefined as above. Representative alkoxy groups include, by way ofexample, methoxy, ethoxy, propoxy, butoxy, and the like.

The term “cycloalkyl” means a monovalent saturated carbocyclic groupwhich may be monocyclic or multicyclic. Unless otherwise defined, suchcycloalkyl groups typically contain from 3 to 10 carbon atoms.Representative cycloalkyl groups include, by way of example,cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl,cyclooctyl, and the like.

The term “halo” means fluoro, chloro, bromo or iodo.

The term “therapeutically effective amount” means an amount sufficientto effect treatment when administered to a patient in need of treatment.

The term “treatment” as used herein means the treatment of a disease,disorder, or medical condition in a patient, such as a mammal(particularly a human) which includes:

-   -   (a) preventing the disease, disorder, or medical condition from        occurring, i.e., prophylactic treatment of a patient;    -   (b) ameliorating the disease, disorder, or medical condition,        i.e., eliminating or causing regression of the disease,        disorder, or medical condition in a patient;    -   (c) suppressing the disease, disorder, or medical condition,        i.e., slowing or arresting the development of the disease,        disorder, or medical condition in a patient; or    -   (d) alleviating the symptoms of the disease, disorder, or        medical condition in a patient.

The term “pharmaceutically-acceptable salt” means a salt prepared froman acid or base which is acceptable for administration to a patient,such as a mammal. Such salts can be derived frompharmaceutically-acceptable inorganic or organic acids and frompharmaceutically-acceptable bases. Typically,pharmaceutically-acceptable salts of compounds of the present inventionare prepared from acids.

Salts derived from pharmaceutically-acceptable acids include, but arenot limited to, acetic, adipic, benzenesulfonic, benzoic,camphorsulfonic, citric, ethanesulfonic, fumaric, gluconic, glutamic,hydrobromic, hydrochloric, lactic, maleic, malic, mandelic,methanesulfonic, mucic, nitric, pantothenic, phosphoric, propionic,salicylic, succinic, sulfuric, tartaric, p-toluenesulfonic, xinafoic(1-hydroxy-2-naphthoic acid), naphthalene-1,5-disulfonic acid and thelike.

The term “solvate” means a complex or aggregate formed by one or moremolecules of a solute, i.e. a compound of the invention or apharmaceutically-acceptable salt thereof, and one or more molecules of asolvent. Such solvates are typically crystalline solids having asubstantially fixed molar ratio of solute and solvent. Representativesolvents include by way of example, water, methanol, ethanol,isopropanol, acetic acid, and the like. When the solvent is water, thesolvate formed is a hydrate.

It will be appreciated that the term “or a pharmaceutically-acceptablesalt or solvate of stereoisomer thereof” is intended to include allpermutations of salts, solvates and stereoisomers, such as a solvate ofa pharmaceutically-acceptable salt of a stereoisomer of a compound offormula (I).

The term “amino-protecting group” means a protecting group suitable forpreventing undesired reactions at an amino nitrogen. Representativeamino-protecting groups include, but are not limited to, formyl; acylgroups, for example alkanoyl groups, such as acetyl; alkoxycarbonylgroups, such as tert-butoxycarbonyl (Boc); arylmethoxycarbonyl groups,such as benzyloxycarbonyl (Cbz) and 9-fluorenylmethoxycarbonyl (Fmoc);arylmethyl groups, such as benzyl (Bn), trityl (Tr), and1,1-di-(4′-methoxyphenyl)methyl; silyl groups, such as trimethylsilyl(TMS) and tert-butyldimethylsilyl (TBDMS); and the like.

General Synthetic Procedures

Compounds of the invention can be prepared from readily availablestarting materials using the following general methods and procedures.Although a particular aspect of the present invention is illustrated inthe schemes below, those skilled in the art will recognize that allaspects of the present invention can be prepared using the methodsdescribed herein or by using other methods, reagents and startingmaterials known to those skilled in the art. It will also be appreciatedthat where typical or preferred process conditions (i.e., reactiontemperatures, times, mole ratios of reactants, solvents, pressures,etc.) are given, other process conditions can also be used unlessotherwise stated. Optimum reaction conditions may vary with theparticular reactants or solvent used, but such conditions can bedetermined by one skilled in the art by routine optimization procedures.

Additionally, as will be apparent to those skilled in the art,conventional protecting groups may be necessary to prevent certainfunctional groups from undergoing undesired reactions. The choice of asuitable protecting group for a particular functional group, as well assuitable conditions for protection and deprotection, are well known inthe art. For example, numerous protecting groups, and their introductionand removal, are described in T. W. Greene and G. M. Wuts, ProtectingGroups in Organic Synthesis, Third Edition, Wiley, New York, 1999, andreferences cited therein.

In one method of synthesis, compounds of formula (I) are prepared asillustrated in Scheme A. (The substituents and variables shown in thefollowing schemes have the definitions provided above unless otherwiseindicated.)

where P¹ represents an amino-protecting group such astert-butoxycarbonyl (Boc) or benzyloxycarbonyl (Cbz).

As shown in Scheme A, the protected aminoazabicyclooctane, or commonly,aminotropane 1 is first reacted with the substituted 1H-indazolecarboxylic acid 2. Typically, this reaction is conducted by firstconverting 2 to an acid chloride by contacting 2 with at least oneequivalent, typically between about 1 and about 2 equivalents of anactivating agent, such as thionyl chloride or oxalyl chloride in anaromatic diluent, such as toluene, benzene, xylene, or the like. Thereaction is typically conducted at a temperature ranging from about 80°C. to about 120° C. for about 15 minutes to about 2 hours, or until thereaction is substantially complete.

The acid chloride solution is typically added to a biphasic mixture ofabout 1 equivalent of the aminotropane 1 to form a protectedintermediate, which is extracted by standard procedures. The biphasicmixture of 1 is generally prepared by dissolving 1 in an aromaticdiluent, such as used above, and adding an aqueous solution containingan excess of base, such as sodium hydroxide or potassium hydroxide, forexample about 2 to 5 equivalents of base.

Alternatively, the amide coupling of intermediate 1 with the carboxylicacid 2 can be performed by converting 2 to an activated ester, such asan N-hydroxy succinimide (NHS) ester or ap-nitrophenyl ester, or an acidimidazole, which is then reacted with aminotropane 1. In yet anotheralternative, the carboxylic acid 2 is reacted with intermediate 1 in thepresence of a coupling agent such as 1,3 dicyclohexylcarbodiimide (DCC),1-(3-dimethylaminopropyl)-3-ethylcarbodiimide (EDC), orbenzotriazol-1-yloxytripyrrolidino-phosphonium hexafluorophosphate(PyBop), optionally combined with 1-hydroxy-7-azabenzotriazole (HOAt).

The protecting group P¹ is removed by standard procedures to provide anintermediate of formula 3. For example, the protecting group Boc, istypically removed by treatment with an acid, such as trifluoroaceticacid. The protecting group Cbz, for example, is conveniently removed byhydrogenolysis over a suitable metal catalyst such as palladium oncarbon.

Intermediate 3 is then reductively N-alkylated by reaction withdimethoxyacetaldehyde to provide an intermediate of formula 4. Thisreaction is typically conducted by contacting 3 with between about 1 andabout 4 equivalents of dimethoxyacetaldehyde in an inert diluent in thepresence of between about 1 and about 2 equivalents of a reducing agent.The reaction is typically conducted at ambient temperature for about 1to about 2 hours, or until the reaction is substantially complete.Suitable inert diluents include dichloromethane, trichloromethane,1,1,2,2-tetrachloroethane, and the like. Typical reducing agents includesodium triacetoxyborohydride, sodium borohydride, and sodiumcyanoborohydride. The product 4 is isolated by standard procedures.

Next, the dimethoxyethyl intermediate 4 is hydrolyzed in an aqueoussolution of a strong acid, for example 3N or 6N HCl, to provide thedihydroxyethyl intermediate 5. It will be understood that whileintermediate 5 is shown in Scheme A in the form of an aldehyde hydrate,intermediate 5 can equivalently be depicted in the form of an aldehyde.The reaction is typically conducted at a temperature in the range ofabout 50° C. to about 100° C. for about 15 minutes to about 2 hours, oruntil the reaction is substantially complete. The product 5 can beisolated in salt form, for example as the HCl salt, or as the neutralspecies after alkaline extraction. Alternatively, the crude intermediate5 can be used in the final step without further manipulation.

Finally the intermediate 5 is reductively coupled with the primary orsecondary amine of the formula H—W, to provide the product of formula(I). Typically, a solution is prepared of between about 1 and about 3equivalents, for example about 2 equivalents, of the amine and areducing agent, such as sodium triacetoxyborohydride or the like, in aninert diluent such as dichloromethane. The intermediate 5 is added tothe amine mixture. The reaction is typically conducted at ambienttemperature for about 15 minutes to about 2 hours, or until the reactionis substantially complete. The crude product of formula (I) is extractedby conventional procedures. The product can be purified in salt form bycrystallization from an inert diluent, for example, ethanol, isopropylalcohol, methanol, acetonitrile, dichloroethane, or mixtures thereof.

Alternatively, compounds of formula (I) can be prepared by N-alkylatinga compound of formula (I) in which R² is hydrogen, which can be preparedaccording to Scheme A. The N-alkylation reaction is typically conductedby contacting a compound of formula (I) in which R² is hydrogen withbetween about 1 and about 4 equivalents of a compound of the formulaL-R² in which L is a leaving group such as iodo or bromo. This reactionis typically conducted in a polar aprotic solvent such asdimethylformamide in the presence of between about 2 and about 4equivalents of strong base, such as potassium tert-butoxide. Typically,the reaction is performed at a temperature of between about 60 and about100° C. for between about 6 and about 24 hours, or until the reaction issubstantially complete.

The protected aminotropane 1 employed in the reactions described in thisapplication is prepared from readily available starting materials. Forexample, when the protecting group P¹ is Boc, the protected endoaminotropane 1′ is prepared by the procedure illustrated in Scheme B.

As described in detail in Example 1a below, to prepare the protectedintermediate 1′, first, 2,5-dimethoxy tetrahydrofuran 6 is contactedwith between about 1 and 2 equivalents, preferably about 1.5 equivalentsof benzyl amine and a slight excess, for example about 1.1 equivalents,of 1,3-acetonedicarboxylic acid 7 in an acidic aqueous solution in thepresence of a buffering agent such as sodium hydrogen phosphate. Thereaction mixture is heated to between about 60 and about 100° C. toensure decarboxylation of any carboxylated intermediates in the product,8-benzyl-8-azabicyclo[3.2.1]octan-3-one 8, commonly N-benzyltropanone.

The intermediate 8 is typically reacted with a slight excess ofdi-tert-butyl dicarbonate (commonly (Boc)₂O), for example, about 1.1equivalents, under a hydrogen atmosphere in the presence of a transitionmetal catalyst to provide the Boc protected intermediate9,3-oxo-8-azabicyclo[3.2.1]octane-8-carboxylic acid tert-butyl ester.The reaction is typically conducted at ambient temperature for about 12to about 72 hours. Finally, intermediate 9 is contacted with a largeexcess, for example at least about 25 equivalents, of ammonium formatein an inert diluent, such as methanol, in the presence of a transitionmetal catalyst to provide the product 1′ in the endo configuration withhigh stereospecificity, for example endo to exo ratio of >99. Thereaction is typically conducted at ambient temperature for about 12 toabout 72 hours or until the reaction is substantially complete. It isadvantageous to add the ammonium formate reagent in portions. Forexample, intermediate 9 is contacted with an initial portion of ammoniumformate of about 15 to about 25 equivalents. After an interval of about12 to about 36 hours, an additional portion of about 5 to about 10equivalents of ammonium formate is added. The subsequent addition can berepeated after a similar interval. The product 1′ can be purified byconventional procedures, such as alkaline extraction.

The 1H-indazole carboxylic acid 2 is readily prepared by proceduresknown in the art, and described, for example, in the literature inHarada et al. Chem. and Pharm Bull. 1995, 43, 1912-30 and in theexamples below.

The amines H—W are available commercially or are readily prepared bystandard procedures from common starting materials.

Further details regarding specific reaction conditions and otherprocedures for preparing representative compounds of the invention orintermediates thereto are described in the examples below.

Accordingly, in a method aspect, the invention provides a process forpreparing a compound of formula (I), or a salt or stereoisomer orprotected derivative thereof, the process comprising reacting a compoundof formula 5 with an amine of the formula H—W to provide a compound offormula (I), or a salt or stereoisomer or protected derivative thereof.

The invention further provides a compound of formula 5, or a salt orstereoisomer or protected derivative thereof, wherein R¹ and R² aredefined as in formula (I).

In an alternative method of synthesis, compounds of formula (I) areprepared by coupling the substituted 1H-indazole carboxylic acid 2 withan intermediate of formula 10 as illustrated in Scheme C.

The reaction of Scheme C is typically conducted under the amide couplingconditions described above for the reaction of the carboxylic acid 2with intermediate 1.

Intermediates of formula 10 can be prepared by deprotecting anintermediate of formula 11

where P¹ represents an amino-protecting group.

Intermediates of formula 11 can be prepared from readily availablestarting materials using procedures analogous to the alkylation,reductive amination, and other reactions described above and/or usingalternative reactions will known to those skilled in the art. Exemplaryprocess routes (i) through (v) for the preparation of intermediate 11are illustrated in Scheme D:

where L denotes a leaving group such as bromo or iodo. In yet anotheralternative method of synthesis, compounds of formula (I) are preparedby coupling an intermediate of formula 3, depicted in Scheme A, with anintermediate of formula 12. It will be understood that whileintermediate 12 is shown in Scheme D in the form of an aldehyde,intermediate 12 can equivalently be depicted in the form of an aldehydehydrate.Pharmaceutical Compositions

The indazole-carboxamide compounds of the invention are typicallyadministered to a patient in the form of a pharmaceutical composition.Such pharmaceutical compositions may be administered to the patient byany acceptable route of administration including, but not limited to,oral, rectal, vaginal, nasal, inhaled, topical (including transdermal)and parenteral modes of administration.

Accordingly, in one of its compositions aspects, the invention isdirected to a pharmaceutical composition comprising apharmaceutically-acceptable carrier or excipient and a therapeuticallyeffective amount of a compound of formula (I) or a pharmaceuticallyacceptable salt thereof. Optionally, such pharmaceutical compositionsmay contain other therapeutic and/or formulating agents if desired.

The pharmaceutical compositions of the invention typically contain atherapeutically effective amount of a compound of the present inventionor a pharmaceutically-acceptable salt thereof. Typically, suchpharmaceutical compositions will contain from about 0.1 to about 95% byweight of the active agent; including from about 1 to about 70% byweight; such as from about 5 to about 60% by weight of the active agent.

Any conventional carrier or excipient may be used in the pharmaceuticalcompositions of the invention. The choice of a particular carrier orexcipient, or combinations of carriers or excipients, will depend on themode of administration being used to treat a particular patient or typeof medical condition or disease state. In this regard, the preparationof a suitable pharmaceutical composition for a particular mode ofadministration is well within the scope of those skilled in thepharmaceutical arts. Additionally, the ingredients for such compositionsare commercially-available from, for example, Sigma, P.O. Box 14508, St.Louis, Mo. 63178. By way of further illustration, conventionalformulation techniques are described in Remington: The Science andPractice of Pharmacy, 20^(th) Edition, Lippincott Williams & White,Baltimore, Md. (2000); and H. C. Ansel et al., Pharmaceutical DosageForms and Drug Delivery Systems, 7^(th) Edition, Lippincott Williams &White, Baltimore, Md. (1999).

Representative examples of materials which can serve as pharmaceuticallyacceptable carriers include, but are not limited to, the following: (1)sugars, such as lactose, glucose and sucrose; (2) starches, such as cornstarch and potato starch; (3) cellulose, such as microcrystallinecellulose, and its derivatives, such as sodium carboxymethyl cellulose,ethyl cellulose and cellulose acetate; (4) powdered tragacanth; (5)malt; (6) gelatin; (7) talc; (8) excipients, such as cocoa butter andsuppository waxes; (9) oils, such as peanut oil, cottonseed oil,safflower oil, sesame oil, olive oil, corn oil and soybean oil; (10)glycols, such as propylene glycol; (11) polyols, such as glycerin,sorbitol, mannitol and polyethylene glycol; (12) esters, such as ethyloleate and ethyl laurate; (13) agar; (14) buffering agents, such asmagnesium hydroxide and aluminum hydroxide; (15) alginic acid; (16)pyrogen-free water; (17) isotonic saline; (18) Ringer's solution; (19)ethyl alcohol; (20) phosphate buffer solutions; and (21) other non-toxiccompatible substances employed in pharmaceutical compositions.

The pharmaceutical compositions of the invention are typically preparedby thoroughly and intimately mixing or blending a compound of theinvention with a pharmaceutically-acceptable carrier and one or moreoptional ingredients. If necessary or desired, the resulting uniformlyblended mixture can then be shaped or loaded into tablets, capsules,pills and the like using conventional procedures and equipment.

The pharmaceutical compositions of the invention are preferably packagedin a unit dosage form. The term “unit dosage form” refers to aphysically discrete unit suitable for dosing a patient, i.e., each unitcontaining a predetermined quantity of active agent calculated toproduce the desired therapeutic effect either alone or in combinationwith one or more additional units. For example, such unit dosage formsmay be capsules, tablets, pills, and the like.

In a preferred embodiment, the pharmaceutical compositions of theinvention are suitable for oral administration. Suitable pharmaceuticalcompositions for oral administration may be in the form of capsules,tablets, pills, lozenges, cachets, dragees, powders, granules; or as asolution or a suspension in an aqueous or non-aqueous liquid; or as anoil-in-water or water-in-oil liquid emulsion; or as an elixir or syrup;and the like; each containing a predetermined amount of a compound ofthe present invention as an active ingredient.

When intended for oral administration in a solid dosage form (i.e., ascapsules, tablets, pills and the like), the pharmaceutical compositionsof the invention will typically comprise a compound of the presentinvention as the active ingredient and one or morepharmaceutically-acceptable carriers, such as sodium citrate ordicalcium phosphate. Optionally or alternatively, such solid dosageforms may also comprise: (1) fillers or extenders, such as starches,microcrystalline cellulose, lactose, sucrose, glucose, mannitol, and/orsilicic acid; (2) binders, such as carboxymethylcellulose, alginates,gelatin, polyvinyl pyrrolidone, sucrose and/or acacia; (3) humectants,such as glycerol; (4) disintegrating agents, such as agar-agar, calciumcarbonate, potato or tapioca starch, alginic acid, certain silicates,and/or sodium carbonate; (5) solution retarding agents, such asparaffin; (6) absorption accelerators, such as quaternary ammoniumcompounds; (7) wetting agents, such as cetyl alcohol and/or glycerolmonostearate; (8) absorbents, such as kaolin and/or bentonite clay; (9)lubricants, such as talc, calcium stearate, magnesium stearate, solidpolyethylene glycols, sodium lauryl sulfate, and/or mixtures thereof;(10) coloring agents; and (11) buffering agents.

Release agents, wetting agents, coating agents, sweetening, flavoringand perfuming agents, preservatives and antioxidants can also be presentin the pharmaceutical compositions of the invention. Examples ofpharmaceutically-acceptable antioxidants include: (1) water-solubleantioxidants, such as ascorbic acid, cysteine hydrochloride, sodiumbisulfate, sodium metabisulfate sodium sulfite and the like; (2)oil-soluble antioxidants, such as ascorbyl palmitate, butylatedhydroxyanisole (BHA), butylated hydroxytoluene (BHT), lecithin, propylgallate, alpha-tocopherol, and the like; and (3) metal-chelating agents,such as citric acid, ethylenediamine tetraacetic acid (EDTA), sorbitol,tartaric acid, phosphoric acid, and the like. Coating agents fortablets, capsules, pills and like, include those used for entericcoatings, such as cellulose acetate phthalate (CAP), polyvinyl acetatephthalate (PVAP), hydroxypropyl methylcellulose phthalate, methacrylicacid-methacrylic acid ester copolymers, cellulose acetate trimellitate(CAT), carboxymethyl ethyl cellulose (CMEC), hydroxypropyl methylcellulose acetate succinate (HPMCAS), and the like.

If desired, the pharmaceutical compositions of the present invention mayalso be formulated to provide slow or controlled release of the activeingredient using, by way of example, hydroxypropyl methyl cellulose invarying proportions; or other polymer matrices, liposomes and/ormicrospheres.

In addition, the pharmaceutical compositions of the present inventionmay optionally contain opacifying agents and may be formulated so thatthey release the active ingredient only, or preferentially, in a certainportion of the gastrointestinal tract, optionally, in a delayed manner.Examples of embedding compositions which can be used include polymericsubstances and waxes. The active ingredient can also be inmicro-encapsulated form, if appropriate, with one or more of theabove-described excipients.

Suitable liquid dosage forms for oral administration include, by way ofillustration, pharmaceutically-acceptable emulsions, microemulsions,solutions, suspensions, syrups and elixirs. Such liquid dosage formstypically comprise the active ingredient and an inert diluent, such as,for example, water or other solvents, solubilizing agents andemulsifiers, such as ethyl alcohol, isopropyl alcohol, ethyl carbonate,ethyl acetate, benzyl alcohol, benzyl benzoate, propylene glycol,1,3-butylene glycol, oils (esp., cottonseed, groundnut, corn, germ,olive, castor and sesame oils), glycerol, tetrahydrofuryl alcohol,polyethylene glycols and fatty acid esters of sorbitan, and mixturesthereof. Suspensions, in addition to the active ingredient, may containsuspending agents such as, for example, ethoxylated isostearyl alcohols,polyoxyethylene sorbitol and sorbitan esters, microcrystallinecellulose, aluminum metahydroxide, bentonite, agar-agar and tragacanth,and mixtures thereof.

Alternatively, the pharmaceutical compositions of the invention areformulated for administration by inhalation. Suitable pharmaceuticalcompositions for administration by inhalation will typically be in theform of an aerosol or a powder. Such compositions are generallyadministered using well-known delivery devices, such as a metered-doseinhaler, a dry powder inhaler, a nebulizer or a similar delivery device.

When administered by inhalation using a pressurized container, thepharmaceutical compositions of the invention will typically comprise theactive ingredient and a suitable propellant, such asdichlorodifluoromethane, trichlorofluoromethane,dichlorotetrafluoroethane, carbon dioxide or other suitable gas.

Additionally, the pharmaceutical composition may be in the form of acapsule or cartridge (made, for example, from gelatin) comprising acompound of the invention and a powder suitable for use in a powderinhaler. Suitable powder bases include, by way of example, lactose orstarch.

The compounds of the invention can also be administered transdermallyusing known transdermal delivery systems and excipients. For example, acompound of the invention can be admixed with permeation enhancers, suchas propylene glycol, polyethylene glycol monolaurate,azacycloalkan-2-ones and the like, and incorporated into a patch orsimilar delivery system. Additional excipients including gelling agents,emulsifiers and buffers, may be used in such transdermal compositions ifdesired.

The following formulations illustrate representative pharmaceuticalcompositions of the present invention:

FORMULATION EXAMPLE A

Hard gelatin capsules for oral administration are prepared as follows:Ingredients Amount Compound of the invention 50 mg Lactose (spray-dried)200 mg  Magnesium stearate 10 mg

-   -   Representative Procedure: The ingredients are thoroughly blended        and then loaded into a hard gelatin capsule (260 mg of        composition per capsule).

FORMULATION EXAMPLE B

Hard gelatin capsules for oral administration are prepared as follows:Ingredients Amount Compound of the invention 20 mg Starch 89 mgMicrocrystalline cellulose 89 mg Magnesium stearate  2 mg

-   -   Representative Procedure: The ingredients are thoroughly blended        and then passed through a No. 45 mesh U.S. sieve and loaded into        a hard gelatin capsule (200 mg of composition per capsule).

FORMULATION EXAMPLE C

Capsules for oral administration are prepared as follows: IngredientsAmount Compound of the invention 10 mg Polyoxyethylene sorbitanmonooleate 50 mg Starch powder 250 mg 

-   -   Representative Procedure: The ingredients are thoroughly blended        and then loaded into a gelatin capsule (310 mg of composition        per capsule).

FORMULATION EXAMPLE D

Tablets for oral administration are prepared as follows: IngredientsAmount Compound of the invention  5 mg Starch 50 mg Microcrystallinecellulose 35 mg Polyvinylpyrrolidone (10 wt. % in water)  4 mg Sodiumcarboxymethyl starch 4.5 mg  Magnesium stearate 0.5 mg  Talc  1 mg

-   -   Representative Procedure: The active ingredient, starch and        cellulose are passed through a No. 45 mesh U.S. sieve and mixed        thoroughly. The solution of polyvinylpyrrolidone is mixed with        the resulting powders, and this mixture is then passed through a        No. 14 mesh U.S. sieve. The granules so produced are dried at        50-60° C. and passed through a No. 18 mesh U.S. sieve. The        sodium carboxymethyl starch, magnesium stearate and talc        (previously passed through a No. 60 mesh U.S. sieve) are then        added to the granules. After mixing, the mixture is compressed        on a tablet machine to afford a tablet weighing 100 mg.

FORMULATION EXAMPLE E

Tablets for oral administration are prepared as follows: IngredientsAmount Compound of the invention 25 mg Microcrystalline cellulose 400mg  Silicon dioxide fumed 10 mg Stearic acid  5 mg

-   -   Representative Procedure: The ingredients are thoroughly blended        and then compressed to form tablets (440 mg of composition per        tablet).

FORMULATION EXAMPLE F

Single-scored tablets for oral administration are prepared as follows:Ingredients Amount Compound of the invention 15 mg Cornstarch 50 mgCroscarmellose sodium 25 mg Lactose 120 mg  Magnesium stearate  5 mg

-   -   Representative Procedure: The ingredients are thoroughly blended        and compressed to form a single-scored tablet (215 mg of        compositions per tablet).

FORMULATION EXAMPLE G

A suspension for oral administration is prepared as follows: IngredientsAmount Compound of the invention 0.1 g Fumaric acid 0.5 g Sodiumchloride 2.0 g Methyl paraben 0.15 g Propyl paraben 0.05 g Granulatedsugar 25.5 g Sorbitol (70% solution) 12.85 g Veegum k (Vanderbilt Co.)1.0 g Flavoring 0.035 mL Colorings 0.5 mg Distilled water q.s. to 100 mL

Representative Procedure: The ingredients are mixed to form a suspensioncontaining 10 mg of active ingredient per 10 mL of suspension.

FORMULATION EXAMPLE H

A dry powder for administration by inhalation is prepared as follows:Ingredients Amount Compound of the invention 1.0 mg Lactose  25 mg

-   -   Representative Procedure: The active ingredient is micronized        and then blended with lactose. This blended mixture is then        loaded into a gelatin inhalation cartridge. The contents of the        cartridge are administered using a powder inhaler.

FORMULATION EXAMPLE I

A dry powder for administration by inhalation in a metered dose inhaleris prepared as follows:

-   -   Representative Procedure: A suspension containing 5 wt. % of a        compound of the invention and 0.1 wt. % lecithin is prepared by        dispersing 10 g of active compound as micronized particles with        mean size less than 10 μm in a solution formed from 0.2 g of        lecithin dissolved in 200 mL of demineralized water. The        suspension is spray dried and the resulting material is        micronized to particles having a mean diameter less than 1.5 μm.        The particles are loaded into cartridges with pressurized        1,1,1,2-tetrafluoroethane.

FORMULATION EXAMPLE J

An injectable formulation is prepared as follows: Ingredients AmountCompound of the invention 0.2 g Sodium acetate buffer solution (0.4 M)40 mL HCl (0.5 N) or NaOH (0.5 N) q.s. to pH 4 Water (distilled,sterile) q.s. to 20 mL

-   -   Representative Procedure: The above ingredients are blended and        the pH is adjusted to 4±0.5 using 0.5 N HCl or 0.5 N NaOH.

FORMULATION EXAMPLE K

Capsules for oral administration are prepared as follows: IngredientsAmount Compound of the Invention 4.05 mg Microcrystalline cellulose(Avicel PH 103) 259.2 mg  Magnesium stearate 0.75 mg

-   -   Representative Procedure: The ingredients are thoroughly blended        and then loaded into a gelatin capsule (Size #1, White, Opaque)        (264 mg of composition per capsule).

FORMULATION EXAMPLE L

Capsules for oral administration are prepared as follows: IngredientsAmount Compound of the Invention 8.2 mg Microcrystalline cellulose(Avicel PH 103) 139.05 mg Magnesium stearate 0.75 mg

-   -   Representative Procedure: The ingredients are thoroughly blended        and then loaded into a gelatin capsule (Size #1, White, Opaque)        (148 mg of composition per capsule).

It will be understood that any form of the compounds of the invention,(i.e. free base, pharmaceutical salt, or solvate) that is suitable forthe particular mode of administration, can be used in the pharmaceuticalcompositions discussed above.

Utility

The indazole-carboxamide compounds of the invention are 5-HT₄ receptoragonists and therefore are expected to be useful for treating medicalconditions mediated by 5-HT₄ receptors or associated with 5-HT₄ receptoractivity, i.e. medical conditions which are ameliorated by treatmentwith a 5-HT₄ receptor agonist. Such medical conditions include, but arenot limited to, irritable bowel syndrome (IBS), chronic constipation,functional dyspepsia, delayed gastric emptying, gastroesophageal refluxdisease (GERD), gastroparesis, diabetic and idiopathic gastropathy,post-operative ileus, intestinal pseudo-obstruction, and drug-induceddelayed transit. In addition, it has been suggested that some 5-HT₄receptor agonist compounds may be used in the treatment of centralnervous system disorders including cognitive disorders, behavioraldisorders, mood disorders, and disorders of control of autonomicfunction.

In particular, the compounds of the invention increase motility of thegastrointestinal (GI) tract and thus are expected to be useful fortreating disorders of the GI tract caused by reduced motility inmammals, including humans. Such GI motility disorders include, by way ofillustration, chronic constipation, constipation-predominant irritablebowel syndrome (C-IBS), diabetic and idiopathic gastroparesis, andfunctional dyspepsia.

In one aspect, therefore, the invention provides a method of increasingmotility of the gastrointestinal tract in a mammal, the methodcomprising administering to the mammal a therapeutically effectiveamount of a pharmaceutical composition comprising apharmaceutically-acceptable carrier and a compound of the invention.

When used to treat disorders of reduced motility of the GI tract orother conditions mediated by 5-HT₄ receptors, the compounds of theinvention will typically be administered orally in a single daily doseor in multiple doses per day, although other forms of administration maybe used. The amount of active agent administered per dose or the totalamount administered per day will typically be determined by a physician,in the light of the relevant circumstances, including the condition tobe treated, the chosen route of administration, the actual compoundadministered and its relative activity, the age, weight, and response ofthe individual patient, the severity of the patient's symptoms, and thelike.

Suitable doses for treating disorders of reduced motility of the GItract or other disorders mediated by 5-HT₄ receptors are expected torange from about 0.0007 to about 20 mg/kg/day of active agent, includingfrom about 0.0007 to about 1 mg/kg/day. For an average 70 kg human, thiswould amount to from about 0.05 to about 70 mg per day of active agent.

In one aspect of the invention, the compounds of the invention are usedto treat chronic constipation. When used to treat chronic constipation,the compounds of the invention will typically be administered orally ina single daily dose or in multiple doses per day. The dose for treatingchronic constipation is expected to range from about 0.05 to about 70 mgper day.

In another aspect of the invention, the compounds of the invention areused to treat irritable bowel syndrome. When used to treatconstipation-predominant irritable bowel syndrome, the compounds of theinvention will typically be administered orally in a single daily doseor in multiple doses per day. The dose for treatingconstipation-predominant irritable bowel syndrome is expected to rangefrom about 0.05 to about 70 mg per day.

In another aspect of the invention, the compounds of the invention areused to treat diabetic gastroparesis. When used to treat diabeticgastroparesis, the compounds of the invention will typically beadministered orally in a single daily dose or in multiple doses per day.The dose for treating diabetic gastroparesis is expected to range fromabout 0.05 to about 70 mg per day.

In yet another aspect of the invention, the compounds of the inventionare used to treat functional dyspepsia. When used to treat functionaldyspepsia, the compounds of the invention will typically be administeredorally in a single daily dose or in multiple doses per day. The dose fortreating functional dyspepsia is expected to range from about 0.05 toabout 70 mg per day.

The invention also provides a method of treating a mammal having adisease or condition associated with 5-HT₄ receptor activity, the methodcomprising administering to the mammal a therapeutically effectiveamount of a compound of the invention or of a pharmaceutical compositioncomprising a compound of the invention.

As described above, compounds of the invention are 5-HT₄ receptoragonists. The invention further provides, therefore, a method ofagonizing a 5-HT₄ receptor in a mammal, the method comprisingadministering a compound of the invention to the mammal. In addition,the compounds of the invention are also useful as research tools forinvestigating or studying biological systems or samples having 5-HT₄receptors, or for discovering new 5-HT₄ receptor agonists. Moreover,since compounds of the invention exhibit binding selectivity for 5-HT₄receptors as compared with binding to receptors of other 5-HT subtypes,particularly 5-HT₃ receptors, such compounds are particularly useful forstudying the effects of selective agonism of 5-HT₄ receptors in abiological system or sample. Any suitable biological system or samplehaving 5-HT₄ receptors may be employed in such studies which may beconducted either in vitro or in vivo. Representative biological systemsor samples suitable for such studies include, but are not limited to,cells, cellular extracts, plasma membranes, tissue samples, mammals(such as mice, rats, guinea pigs, rabbits, dogs, pigs, etc.) and thelike.

In this aspect of the invention, a biological system or samplecomprising a 5-HT₄ receptor is contacted with a 5-HT₄ receptor-agonizingamount of a compound of the invention. The effects of agonizing the5-HT₄ receptor are then determined using conventional procedures andequipment, such as radioligand binding assays and functional assays.Such functional assays include ligand-mediated changes in intracellularcyclic adenosine monophosphate (cAMP), ligand-mediated changes inactivity of the enzyme adenylyl cyclase (which synthesizes cAMP),ligand-mediated changes in incorporation of analogs of guanosinetriphosphate (GTP), such as [³⁵S]GTPγS (guanosine5′-O-(γ-thio)triphosphate) or GTP-Eu, into isolated membranes viareceptor catalyzed exchange of GTP analogs for GDP analogs,ligand-mediated changes in free intracellular calcium ions (measured,for example, with a fluorescence-linked imaging plate reader or FLIPR®from Molecular Devices, Inc.), and measurement of mitogen activatedprotein kinase (MAPK) activation. A compound of the invention mayagonize or increase the activation of 5-HT₄ receptors in any of thefunctional assays listed above, or assays of a similar nature. A 5-HT₄receptor-agonizing amount of a compound of the invention will typicallyrange from about 1 nanomolar to about 500 nanomolar.

Additionally, the compounds of the invention can be used as researchtools for discovering new 5-HT₄ receptor agonists. In this embodiment,5-HT₄ receptor binding or functional data for a test compound or a groupof test compounds is compared to the 5-HT₄ receptor binding orfunctional data for a compound of the invention to identify testcompounds that have superior binding or functional activity, if any.This aspect of the invention includes, as separate embodiments, both thegeneration of comparison data (using the appropriate assays) and theanalysis of the test data to identify test compounds of interest.

Among other properties, compounds of the invention have been found to bepotent agonists of the 5-HT₄ receptor and to exhibit substantialselectivity for the 5-HT₄ receptor subtype over the 5-HT₃ receptorsubtype in radioligand binding assays. Further, compounds of theinvention have demonstrated superior pharmacokinetic properties in a ratmodel. Compounds of the invention are thus expected to be highlybioavailable upon oral administration. In addition, these compounds havebeen shown not to inhibit the potassium ion current in an in vitrovoltage-clamp model using isolated whole cells expressing the hERGcardiac potassium channel. The voltage-clamp assay is an acceptedpre-clinical method of assessing the potential for pharmaceutical agentsto change the pattern of cardiac repolarization, specifically to cause,so-called QT prolongation, which has been associated with cardiacarrhythmia. (Cavero et al., Opinion on Pharmacotherapy, 2000, 1, 947-73,Fernini et al., Nature Reviews Drug Discovery, 2003, 2, 439-447)Accordingly, pharmaceutical compositions comprising compounds of theinvention are expected to be free of such cardiac side effects.

There properties, as well as the utility of the compounds of theinvention, can be demonstrated using various in vitro and in vivo assayswell-known to those skilled in the art. Representative assays aredescribed in further detail in the following examples.

EXAMPLES

The following synthetic and biological examples are offered toillustrate the invention, and are not to be construed in any way aslimiting the scope of the invention. In the examples below, thefollowing abbreviations have the following meanings unless otherwiseindicated. Abbreviations not defined below have their generally acceptedmeanings. Boc = tert-butoxycarbonyl (Boc)₂O = di-tert-butyl dicarbonateDCM = dichloromethane DMF = N,N-dimethylformamide DMSO = dimethylsulfoxide EtOAc = ethyl acetate mCPBA = m-chlorobenzoic acid MeCN =acetonitrile MTBE = tert-butyl methyl ether PyBop =benzotriazol-1-yloxytripyrrolidino- phosphonium hexafluorophosphateR_(f) = retention factor RT = room temperature TFA = trifluoroaceticacid THF = tetrahydrofuran

Reagents (including secondary amines) and solvents were purchased fromcommercial suppliers (Aldrich, Fluka, Sigma, etc.), and used withoutfurther purification. Reactions were run under nitrogen atmosphere,unless noted otherwise. Progress of reaction mixtures was monitored bythin layer chromatography (TLC), analytical high performance liquidchromatography (anal. HPLC), and mass spectrometry, the details of whichare given below and separately in specific examples of reactions.Reaction mixtures were worked up as described specifically in eachreaction; commonly they were purified by extraction and otherpurification methods such as temperature-, and solvent-dependentcrystallization, and precipitation. In addition, reaction mixtures wereroutinely purified by preparative HPLC: a general protocol is describedbelow. Characterization of reaction products was routinely carried outby mass and ¹H-NMR spectrometry. For NMR measurement, samples weredissolved in deuterated solvent (CD₃OD, CDCl₃, or DMSO-d₆), and ¹H-NMRspectra were acquired with a Varian Gemini 2000 instrument (300 MHz)under standard observation conditions. Mass spectrometric identificationof compounds was performed by an electrospray ionization method (ESMS)with an Applied Biosystems (Foster City, Calif.) model API 150 EXinstrument or an Agilent (Palo Alto, Calif.) model 1100 LC/MSDinstrument.

General Protocol for Analytical HPLC

Crude compounds were dissolved in 50% MeCN/H₂O (with 0.1% TFA) at0.5-1.0 mg/mL concentration, and analyzed using the followingconditions:

-   -   Column: Zorbax Bonus-RP (3.5 μm of particle size, 2.1×50 mm)    -   Flow rate: 0.5 mL/min    -   Detector wavelength: 214, 254, and 280 nm.        General Protocol for Preparative HPLC Purification

Crude compounds were dissolved in 50% acetic acid in water at 50-100mg/mL concentration, filtered, and fractionated using the followingprocedure:

-   -   Column: YMC Pack-Pro C18 (50a×20 mm; ID=5 μm)    -   Flow rate: 40 mL/min    -   Mobile Phases:        -   A=90% MeCN/10% H₂O/0.1% TFA        -   B=98% H₂O/2% MeCN/0.1% TFA    -   Gradient: 10% A/90% B to 50% A/50% B over 30 min (linear)    -   Detector wavelength: 214 nm.        Preparation of Secondary Amines

Thiomorpholine-1,1-dioxide was prepared from thiomorpholine byprotection of the secondary amine to N-Boc thiomorpholine ((Boc)₂O,MeOH), oxidation to sulfone (mCPBA, CH₂Cl₂, 0° C.), and deprotection ofthe N-Boc group to provide the free amine (CF₃CO₂H, CH₂Cl₂). (m/z):[M+H]⁺ calcd for C₄H₉NO₂S, 136.04; found, 135.9.

The N-sulfonyl derivatives of piperazine were prepared from N-Bocpiperazine by reacting with respective sulfonyl chloride (iPr₂NEt,CH₂Cl₂, 0° C.), and deprotecting the N-Boc group (CF₃CO₂H, CH₂Cl₂).1-Methanesulfonyl-piperazine: ¹H-NMR (CDCl₃; neutral): δ (ppm) 3.1 (t,4H), 2.9 (t, 4H), 2.7 (s, 3H).1-(Methylsulfonyl)methanesulfonyl-piperazine: ¹H-NMR (CD₃OD): δ (ppm)2.90 (s, 3H), 3.02 (m, 4H), 3.38 (m, 4H), 4.61 (s, 2H).

The racemic or single chiral isomer forms of 3-acetylaminopyrrolidinewere prepared by treating N¹-Boc-3-aminopyrrolidine (racemate, 3R, or3S) with acetyl chloride (iPr₂NEt, CH₂Cl₂, 0° C.), and deprotecting theN-Boc group (CF₃CO₂H, CH₂Cl₂). 3-(Acetamido)pyrrolidine: ¹H-NMR(DMSO-d₆; TFA salt): δ (ppm) 4.2 (quin, 1H), 3.3-3.1 (m, 3H), 2.9 (m,1H), 2.0 (m, 1H), 1.8 (br s, 4H).

3-((R)-2-Hydroxypropionamido)pyrrolidine was prepared after amidation ofN¹-Boc-3-aminopyrrolidine (L-lactic acid, PyBOP, DMF, RT), anddeprotection of N-Boc group (CF₃CO₂H, CH₂Cl₂). (m/z): [M+H]⁺ calcd forC₇H₁₄N₂O₂, 159.11; found, 159.0. ¹H-NMR (CD₃OD; TFA salt): δ (ppm) 4.4(quin, 1H), 4.1 (q, 1H), 3.5-3.4 (m, 2H), 3.3-3.2 (m, 2H), 2.3 (m, 1H),2.0 (m, 1H), 1.3 (d, 3H).

The N³-alkanesulfonyl derivatives of (3R)-aminopyrrolidine were obtainedby treating N¹-Boc-(3R)-aminopyrrolidine with propionylsulfonyl chlorideor cyclohexylmethylsulfonyl chloride (i-Pr₂NEt, CH₂Cl₂, 0° C.), anddeprotecting N-Boc group (CF₃CO₂H, CH₂Cl₂).

3-(N-Acetyl-N-methylamido)piperidine was prepared from N³-Cbz protected3-amino-piperidine-1-carboxylic acid t-butyl ester (De Costa, B., et al.J. Med. Chem. 1992, 35, 4334-43) after four synthetic steps: i) MeI,n-BuLi, THF, −78° C. to rt; ii) H₂ (1 atm), 10% Pd/C, EtOH; iii) AcCl,i-Pr₂NEt, CH₂Cl₂; iv) CF₃CO₂H, CH₂Cl₂. m/z: [M+H]⁺ calcd for C₈H₆N₂O:157.13; found, 157.2. ¹H-NMR (CD₃OD; TFA salt): δ (ppm) 4.6 (m, 1H), 3.3(m, 1H), 3.2 (m, 1H), 3.0 (m, 1H), 2.9 (s, 3H), 2.8 (m, 1H), 2.0 (s,3H), 1.9-1.7 (m, 4H).

3-(N-Acetyl-amido)piperidine was prepared from3-amino-piperidine-1-carboxylic acid tert-butyl ester afterN-acetylation and deprotection of the N-Boc group: i) AcCl, i-Pr₂NEt,CH₂Cl₂; ii) CF₃CO₂H, CH₂Cl₂. ¹H-NMR (CD₃OD; TFA salt): δ (ppm) 3.9 (m,1H), 3.3 (dd, 1H), 3.2 (m, 1H), 2.9 (dt, 1H), 2.75 (dt, 1H), 2.0-1.9 (m,2H), 1.9 (s, 3H), 1.8-1.4 (m, 2H).

The N³-alkanesulfonyl derivatives of 3-aminopiperidine were synthesizedby reacting the chiral or racemic forms of3-amino-piperidine-1-carboxylxic acid tert-butyl ester with therespective alkanesulfonyl chloride (i-Pr₂NEt, CH₂Cl₂) and deprotectingthe N-Boc group (CF₃CO₂H, CH₂Cl₂).(3S)-3-(ethanesulfonylamido)piperidine: ¹H-NMR (CD₃OD): δ (ppm) 1.29(t,3H, J₁=7.4 Hz), 1.50-1.80 (m, 2H), 1.90-2.10 (m, 2H), 2.89 (m, 2H), 3.05(q, 2H, J₁=7.4 Hz), 3.27 (m, 2H), 3.40 (d of d (br), 1H), 3.52 (m, 1H).3S-Methylsulfonylmethanesulfonylamido-piperidine: ¹H-NMR (CD₃OD): δ(ppm) 2.13-2.30 (m, 2H), 2.40-2.57 (m, 2H), 2.98 (m, 2H), 3.15 (s, 3H),3.21 (m, 2H), 3.30 (br d, 1H), 3.74 (m, 1H).

3-(Methylamino)-1-acetylpyrrolidine was prepared from3-(methylamino)-1-benzylpyrrolidine (TCI America) after four steps: i)(Boc)₂O, MeOH, rt; ii) H₂ (1 atm), 10% Pd/C, EtOH; iii) AcCl, i-Pr₂NEt,CH₂Cl₂; iv) CF₃CO₂H, CH₂Cl₂. (m/z): [M+H]⁺ calcd for C₇H₁₄N₂O: 143.12;found, 143.0.

3-(Methylamino)-1-(methanesulfonyl)pyrrolidine was prepared from3-(methylamino)-1-benzylpyrrolidine after four steps: i) (Boc)₂O, MeOH,rt; ii) H₂ (1 atm), 10% Pd/C, EtOH; iii) CH₃SO₂Cl, i-Pr₂NEt, CH₂Cl₂; iv)CF₃CO₂H, CH₂Cl₂. (m/z): [M+H]⁺ calcd for C₆H₁₄N₂O₂S: 179.08; found,179.2. 3R-Methylamino-1-(methanesulfonyl)pyrrolidine was prepared in asimilar manner from (3R)-(methylamino)-1-benzylpyrrolidine.

Derivatives of tetrahydro-3-thiophenamine-1,1-dioxide were preparedfollowing the protocol of Loev, B. J. Org. Chem. 1961, 26, 4394-9 byreacting 3-sulfolene with a requisite primary amine in methanol (cat.KOH, rt). N-Methyl-3-tetrahydrothiopheneamine-1,1-dioxide (TFA salt):¹H-NMR (DMSO-d₆): δ (ppm) 9.4 (br s, 2H), 4.0-3.8 (quin, 1H), 3.6-3.5(dd, 1H), 3.4-3.3 (m, 1H), 3.2-3.1 (m, 2H), 2.5 (s, 3H), 2.4 (m, 1H),2.1 (m, 1H).N-2-(1-hydroxy)ethyl-3-tetrahydrothiopheneamine-1,1-dioxide: (m/z):[M+H]⁺ calcd for C₆H₁₃NO₃S: 180.07; found, 180.2.

N-Methyl-tetrahydro-2H-thiopyran-4-amine-1,1-dioxide was prepared fromtetrahydro-4H-thiopyran-4-one: i) MeNH₂, NaBH₄; ii) (Boc)₂O, MeOH; iii)mCPBA, CH₂Cl₂, 0° C.; iv) CF₃CO₂H, CH₂Cl₂. (m/z): [M+H]⁺ calcd forC₆H₁₃NO₂S 164.07; found, 164.9. ¹H-NMR (CD₃OD; TFA salt): δ (ppm)3.4-3.1 (m, 5H), 2.7 (s, 3H), 2.4 (br d, 2H), 2.1 (br m, 2H).

1-Acetyl-3-(methylamino)piperidine was prepared from N³-Cbz protected3-methylamino-piperidine: i) AcCl, i-Pr₂NEt, CH₂Cl₂; ii) H₂ (1 atm), 10%Pd/C, EtOH. ¹H-NMR (CD₃OD): δ (ppm) 4.0 (m, 1H), 3.6 (m, 1H), 3.4-3.2(m, 2H), 3.0 (m, 1H), 2.6 (s, 3H), 2.1 (s, 3H), 1.8-1.6 (m, 4H).

1-(Methanesulfonyl)-3-(methylamino)piperidine was prepared from N³-Cbzprotected 3-methylamino-piperidine: i) CH₃SO₂Cl, i-Pr₂NEt, CH₂Cl₂; ii)H₂ (1 atm), 10% Pd/C, EtOH. (m/z): [M+H]⁺ calcd for C₇H₁₆N₂O₂S 193.10;found, 193.0. ¹H-NMR (DMSO-d₆; TFA salt): δ (ppm) 3.4 (dd, 1H), 3.2 (m,2H), 3.10 (s, 3H), 3.0-2.9 (m, 2H), 2.8 (s, 3H), 1.85-1.75 (m, 2H),1.6-1.4 (m, 2H).

EXAMPLE 1 Synthesis of 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide

a. Preparation of 8-benzyl-8-azabicyclo[3.2.1]octan-3-one

Concentrated hydrochloric acid (30 mL) was added to a heterogeneoussolution of 2,5-dimethoxy tetrahydrofuran (82.2 g, 0.622 mol) in water(170 mL) while stirring. In a separate flask cooled to 0° C. (ice bath),concentrated hydrochloric acid (92 mL) was added slowly to a solution ofbenzyl amine (100 g, 0.933 mol) in water (350 mL). The2,5-dimethoxytetrahydrofuran solution was stirred for approximately 20min, diluted with water (250 mL), and then the benzyl amine solution wasadded, followed by the addition of a solution of 1,3-acetonedicarboxylicacid (100 g, 0.684 mol) in water (400 mL) and then the addition ofsodium hydrogen phosphate (44 g, 0.31 mol) in water (200 mL). The pH wasadjusted from pH 1 to pH˜4.5 using 40% NaOH. The resulting cloudy andpale yellow solution was stirred overnight. The solution was thenacidified to pH 3 from pH 7.5 using 50% hydrochloric acid, heated to 85°C. and stirred for 2 hours. The solution was cooled to room temperature,basified to pH 12 using 40% NaOH, and extracted with dichloromethane(3×500 mL). The combined organic layers were washed with brine, dried(MgSO₄), filtered and concentrated under reduced pressure to produce thecrude title intermediate as a viscous brown oil (52 g).

To a solution of the crude intermediate in methanol (1000 mL) was addeddi-tert-butyl dicarbonate (74.6 g, 0.342 mol) at 0° C. The solution wasallowed to warm to room temperature and stirred overnight. The methanolwas removed under reduced pressure and the resulting oil was dissolvedin dichloromethane (1000 mL). The intermediate was extracted into 1 MH₃PO₄ (1000 mL) and washed with dichloromethane (3×250 mL) The aqueouslayer was basified to pH 12 using aqueous NaOH, and extracted withdichloromethane (3×500 mL). The combined organic layers were dried(MgSO₄), filtered and concentrated under reduced pressure to produce thetitle intermediate as a viscous, light brown oil (54 g). ¹H-NMR (CDCl₃)δ (ppm) 7.5-7.2 (m, 5H, C₆H₅), 3.7 (s, 2H, CH₂Ph), 3.45 (broad s, 2H,CH-NBn), 2.7-2.6 (dd, 2H, CH₂CO), 2.2-2.1 (dd, 2H, CH₂CO), 2.1-2.0 (m,2H, CH₂CH₂), 1.6 (m, 2H, CH₂CH₂). (m/z): [M+H]⁺ calcd for C₁₄H₁₇NO216.14; found, 216.0.

b. Preparation of 3-oxo-8-azabicyclo[3.2.1]octane-8-carboxylic acidtert-butyl ester

To a solution of 8-benzyl-8-azabicyclo[3.2.1]octan-3-one (75 g, 0.348mol) in EtOAc (300 mL) was added a solution of di-tert-butyl dicarbonate(83.6 g, 0.383 mol, 1.1 eq) in EtOAc (300 mL). The resulting solutionand rinse (100 mL EtOAc) was added to a 1 L Parr hydrogenation vesselcontaining 23 g of palladium hydroxide (20 wt. % Pd, dry basis, oncarbon, ˜50% wet with water; e.g. Pearlman's catalyst) under a stream ofnitrogen. The reaction vessel was degassed (alternating vacuum and N₂five times) and pressurized to 60 psi of H₂ gas. The reaction solutionwas agitated for two days and recharged with H₂ as needed to keep the H₂pressure at 60 psi until the reaction was complete as monitored bysilica thin layer chromatography. The black solution was then filteredthrough a pad of Celite® and concentrated under reduced pressure toyield the title intermediate quantitatively as a viscous, yellow toorange oil (51 g). It was used in the next step without furthertreatment. ¹H NMR (CDCl₃) δ (ppm) 4.5 (broad, 2H, CH-NBoc), 2.7 (broad,2H, CH₂CO), 2.4-2.3 (dd, 2H, CH₂CH₂), 2.1 (broad m, 2H, CH₂CO), 1.7-1.6(dd, 2H, CH₂CH₂), 1.5 (s, 9H, (CH₃)₃COCON)).

c. Preparation of(1S,3R,5R)-3-amino-8-azabicyclo[3.2.1]octane-8-carboxylic acidtert-butyl ester

To a solution of the product of the previous step (75.4 g, 0.335 mol) inmethanol (1 L) was added ammonium formate (422.5 g, 6.7 mol), water (115mL) and 65 g of palladium on activated carbon (10% on dry basis, ˜50%wet with water; Degussa type E101NE/W) under a stream of N₂ whilestirring via mechanical stirrer. After 24 and 48 hours, additionalportions of ammonium formate (132 g, 2.1 mol) were added each time. Oncereaction progression ceased, as monitored by anal. HPLC, Celite® (>500g) was added and the resulting thick suspension was filtered and thenthe collected solid was rinsed with methanol (˜500 mL). The filtrateswere combined and concentrated under reduced pressure until all methanolhad been removed. The resulting cloudy, biphasic solution was thendiluted with 1M phosphoric acid to a final volume of 1.5 to 2.0 L at pH2 and washed with dichloromethane (3×700 mL). The aqueous layer wasbasified to pH 12 using 40% aq. NaOH, and extracted with dichloromethane(3×700 mL). The combined organic layers were dried over MgSO₄, filtered,and concentrated by rotary evaporation, then high-vacuum leaving 52 g(70%) of the title intermediate, commonly N-Boc-endo-3-aminotropane, asa white to pale yellow solid. The isomer ratio of endo to exo amine ofthe product was >99 based on ¹H-NMR analysis (>96% purity by analyticalHPLC). ¹H NMR (CDCl₃) δ (ppm) 4.2-4.0 (broad d, 2H, CHNBoc), 3.25 (t,1H, CHNH₂), 2.1-2.05 (m, 4H), 1.9 (m, 2H), 1.4 (s, 9H, (CH₃)₃OCON),1.2-1.1 (broad, 2H). (m/z): [M+H]⁺ calcd for C₁₂H₂₂N₂O₂ 227.18; found,227.2. Analytical HPLC (isocratic method; 2:98 (A:B) to 90:10 (A:B) over5 min): retention time=2.14 min.

d. Preparation of 1-isopropyl-1H-indazole-3-carboxylic acid

To indazole-3-carboxylic acid (40 g, 247 mmol) suspended in methanol(700 mL) was added concentrated H₂SO₄ (10 mL) slowly while stirring themixture. The mixture was stirred and refluxed at 80° C. for 24 h. Themixture was cooled, filtered, and concentrated under reduced pressure toafford a pale yellow solid. The solid was suspended in water (700 mL),crushed to fine powder, collected by filtration, and rinsed with water(˜400 mL). The product was suspended in toluene, and evaporated todryness under reduced pressure, affording indazole-3-carboxylic acidmethyl ester as a pale yellow solid (45 g, >95% pure). (m/z): [M+H]⁺calcd for C₉H₈N₂O₂ 177.07; found, 177.0. ¹H-NMR (CD₃OD, 300 MHz): δ(ppm) 8.0 (1H, d), 7.5 (1H, d), 7.4 (1H, t), 7.2 (1H, t), 3.9 (3H, s).

To a solution of indazole-3-carboxylic acid methyl ester (40.7 g, 231mmol) in anhydrous tetrahydrofuran (700 mL) cooled in an ice bath wasadded slowly solid potassium tert-butoxide (28.3 g, 252 mmol). Themixture was stirred at the same temperature for 1 hr prior to theaddition of 2-iododopropane (34.4 mL, 367 mmol). The final mixture wasstirred for 12 h at ambient temperature, and refluxed for 12 h. Aftercooling to room temperature, the mixture was filtered, and the collectedsolid was rinsed with tetrahydrofuran (100 mL). The filtrates werecombined, and concentrated to dryness under reduced pressure, affordingcrude 1-isopropyl-1H-indazole-3-carboxylic acid methyl ester (49.7 g) asa pale yellow oil. The crude material was purified by flash silica gelchromatography eluting with hexane/ethyl acetate (9/1 to 3/1) to yield1-isopropyl-1H-indazole-3-carboxylic acid methyl ester (43 g, 197mmol, >99% pure). ¹H-NMR (CD₃OD, 300 MHz): δ (ppm) 8.1-8.0 (1H, d), 7.6(1H, d), 7.4 (1H, t), 7.2 (1H, t), 5.0 (1H, quin), 3.9 (s, 3H), 1.5 (6H,d).

To a solution of the methyl ester dissolved in tetrahydrofuran (400 mL)was added 1M NaOH (400 mL). The mixture was stirred for 24 h at ambienttemperature. The reaction was terminated by washing with ethyl acetate(2×400 mL), saving the aqueous layer. The aqueous layer was acidifiedslowly by adding conc. HCl (˜40 mL) in an ice bath, which led toseparation of a pale yellow oily product. The product was extracted withethyl acetate (1000 mL), and the organic layer was dried over MgSO₄ andevaporated under reduced pressure to yield the title intermediate as apale yellow to white solid (34 g, >98% pure), which was further purifiedby crystallization from ethyl acetate to provide the title intermediateas colorless needles. (m/z): [M+Na]⁺ calcd for C₁₁H₁₂N₂O₂ 226.07; found,226.6. ¹H-NMR (CD₃OD, 300 MHz):): δ (ppm) 8.1-8.0 (1H, d), 7.6 (1H, d),7.4 (1H, t), 7.2 (1H, t), 5.0 (1H, quin), 1.5 (6H, d).

e. Preparation of(1S,3R,5R)-3-[1-isopropyl-1H-indazole-3-carbonyl)amino]-8-azabicyclo[3.2.1]octane-8-carboxylicacid tert-butyl ester

A suspension of 1-isopropyl-1H-indazole-3-carboxylic acid (56.35 g;0.276 mol) in toluene (500 mL) was stirred and heated for 5 min prior tothe addition of thionyl chloride (30.2 mL; 0.414 mol). After heating at100° C. for 15 min, the mixture became a homogeneous solution, whichcontinued to be stirred at the same temperature for an additional 90min. In a separate reaction flask,(1S,3R,5R)-3-amino-8-azabicyclo[3.2.1]octane-8-carboxylic acidtert-butyl ester, prepared as in step c, (62.43 g; 0.276 mol) wasdissolved in 250 mL of toluene and followed by addition of NaOH (66.3 g)dissolved in 250 mL of water. This biphasic mixture was cooled in an icebath. The solution of indazole acid chloride prepared above was cooledto room temperature, and added over 15 min to the biphasic solution,which was stirred vigorously in an ice bath. After stirring for 1.5 h,the reaction mixture was transferred to a separatory funnel. First, theaqueous layer was separated from toluene layer (saved), and extractedwith EtOAc (2×500 mL). The toluene layer was concentrated under reducedpressure, and the obtained residue was dissolved in the organic extract(1 L; EtOAc). The solution was washed with 1 M H₃PO₄ (400 mL), sat.NaHCO₃ (400 mL), and then brine solution (400 mL). After drying overMgSO₄, the organic solution was evaporated to dryness under reducedpressure, yielding 119.2 g of the title intermediate. ¹H-NMR (DMSO-d₆):δ (ppm) 1.41 (s, 9H), 1.51 (d, 6H), 1.82 (m, 2H), 1.97 (bs, 4H), 2.09(m, 2H), 4.10 (m, 3H), 5.10 (sept, 1H), 7.23 (t, 1H), 7.42 (t, 1H), 7.79(d, 1H), 7.82 (d, 1H), 8.18 (d, 1H). (m/z): [M+H]⁺ calcd for C₂₃H₃₂N₄O₃,413.26; found, 413.1. Retention time (anal. HPLC: 2-95% MeCN/H₂O over 6min)=4.85 min.

-   -   f. Preparation of 1-isopropyl-1H-indazole-3-carboxylic acid        {(1S,3R,5R)-8-azabicyclo[3.2.1]oct-3-yl}amide

The product for the previous step was solubilized in dichloromethane(200 mL), cooled in an ice bath, and then mixed with 200 mL oftrifluoroacetic acid. The reaction mixture was stirred for 1 h atambient temperature. It was then added dropwise to ethyl ether (2 L) ina flask while being stirred, which afforded the title intermediate asits mono(trifluoroacetic acid) salt (102.7 g after drying, 87% yieldover two steps). ¹H-NMR (DMSO-d₆): δ (ppm) 1.54 (d, 6H), 2.05 (m, 2H),2.24 (m, 6H), 4.03 (s, 2H), 4.12 (q, 1H), 5.09 (sept, 1H), 7.28 (t, 1H),7.45 (t, 1H), 7.81 (d, 1H), 8.00 (d, 1H), 8.11 (d, 1H), 8.54 (bd, 2H).(m/z): [M+H]⁺ calcd for C₁₈H₂₄N₄O, 313.20; found, 313.1. Retention time(anal. HPLC: 2-95% MeCN/H₂O over 6 min)=2.65 min.

g. Preparation of 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-(2,2-dimethoxyethyl)-8-aza-bicyclo[3.2.1]oct-3-yl}amide

To a solution of 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-aza-bicyclo[3.2.1]oct-3-yl}amide (52.7 g; 0.124 mol)dissolved in 500 mL of dichloromethane was added diisopropylethylamine(43.1 mL) and dimethoxy acetaldehyde in tert-butyl methyl ether (conc45%; 44.5 mL, 0.173 mmol). After stirring 35 min at ambient temperature,sodium triacetoxyborohydride (36.7 g; 0.173 mol) was added to thismixture. The reaction was quenched after 90 min by adding slowly water(50 mL) and sat. NaHCO₃ solution (100 mL) in an ice bath. The mixturewas diluted with 500 mL of dichloromethane, and transferred to aseparatory funnel. The organic layer was collected, and washed with sat.NaHCO₃ (250 mL), and brine solution (350 mL). It was dried over MgSO₄,and evaporated under reduced pressure, yielding the title intermediate(58.8 g). ¹H-NMR (CDCl₃): δ (ppm) 1.60 (d, 6H), 1.77 (m, 2H), 1.96-2.09(m, 4H), 2.29 (m, 2H), 2.55 (m, 2H), 3.33 (m, 2H), 3.41 (s, 6H), 4.33(q, 1H), 4.47 (m, 1H), 4.87 (sept, 1H), 7.26 (t, 1H), 7.37-7.46 (m, 2H),7.56 (d, 1H), 8.36 (d, 1H). (m/z): [M+H]⁺ calcd for C₂₂H₃₂N₄O₃ 401.26;found, 401.3. Retention time (anal. HPLC: 2-50% MeCN/H₂O over 6min)=4.20 min.

h. Preparation of 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-(2,2-dihydroxyethyl)-8-aza-bicyclo[3.2.1]oct-3-yl}amide

The product of the previous step (55.2 g) was suspended in 500 mL of 6 Mhydrochloric acid and heated at 70° C. for 1 h. The reaction mixture wascooled to 0° C., and diluted with dichloromethane (500 mL) prior tobasification of the aqueous layer by slow addition of 6M NaOH (800 mL).It was further mixed with 800 mL of dichloromethane, and transferred toa separatory funnel. The organic layer was collected, washed with brine,dried over MgSO₄, and evaporated to dryness affording the titleintermediate (45.1 g). (m/z): [M+H]⁺ calcd for C₂₀H₂₈N₄O₃, 373.22;found, 373.2. Retention time (anal. HPLC: 2-50% MeCN/H₂O over 6min)=3.77 min.

i. Synthesis 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-aza-bicyclo[3.2.1]oct-3-yl}amide,alternatively,N-[(3-endo)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl]-1-(1-methylethyl)-1H-indazole-3-carboxamide

To a flask containing 450 mL of dichloromethane was added1-acetylpiperazine (19.3 g; 0.151 mol), sodium triacetoxyborohydride(34.4 g). It was stirred for 5 min prior to addition of the product ofthe previous step (45.1 g). The final mixture was stirred for 1 h, atwhich time the reaction was complete based on HPLC and massspectrometric analysis. Water (200 mL) was added slowly and the mixturewas diluted with 600 mL of dichloromethane, and shaken in a funnelbefore collecting the organic layer. It was washed with 1M NaOH (400 mL)and brine (500 mL). Drying over MgSO₄, and evaporation afforded thetitle compound as a colorless solid (47.6 g). The crude product waspurified by crystallization from ethanol as the HCl salt (>30 g;purity>98%). ¹H-NMR (DMSO-d₆; free base): δ (ppm) 1.52 (d, 6H), 1.69 (m,2H), 1.83 (m, 2H), 1.97 (s, 3H), 1.92-2.10 (m, 4H), 2.33 (t, 2H), 2.42(m, 6H), 2.50 (m, 2H), 3.21 (bs, 2H), 3.38 (m, 4H), 4.09 (q, 1H), 5.07(sept, 1H), 7.26 (t, 1H), 7.43 (t, 1H), 7.79 (d, 1H), 8.12 (d, 1H).(m/z): [M+H]⁺ calcd for C₂₆H₃₈N₆O₂, 467.31; found, 467.5. Retention time(anal. HPLC: 2-50% MeCN/H₂O over 6 min)=3.52 min.

EXAMPLE 2 Synthesis of 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-(tetrahydrofuran-2-carbonyl)piperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide

To a solution of N-[2-tetrahydrofuroyl]piperazine hydrobromide (40 mg,0.15 mmol) and N,N-diisopropylethylamine (12 μL, 0.3 mmol) indichloromethane (1.5 mL) was added sodium triacetoxyborohydride (64 mg,0.3 mmol), and then 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-(2,2-dihydroxyethyl)-8-azabicyclo[3.2.1]oct-3-yl}amide(HCl salt) (39 mg, 0.1 mmol). The mixture was shaken at ambienttemperature for 15 min. After concentration under reduced pressure, thereaction mixture was dissolved in 50% aqueous acetic acid, and purifiedby preparative HPLC to provide the trifluroacetic acid salt of the titlecompound (97% purity). (m/z): [M+H]⁺ calcd for C₂₉H₄₂N₆O₃, 523.34; found523.2. Retention time (anal. HPLC: 5-65% MeCN/H₂O over 5 min)=2.7 min.

EXAMPLES 3-20

Using processes similar to that of Example 2, except replacing theN-[2-tetrahydrofuroyl]piperazine hydrobromide with the appropriatesecondary amine, the compounds of Examples 3-20 were prepared.

Example 3 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(1,1-dioxo-1λ⁶-thiomorpholin-4-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;(m/z): [M+H]+calcd for C₂₄H₃₅N₅O₃S, 474.25; found 474.2. Retention time(anal. HPLC: 5-75% MeCN/H₂O over 5 min)=2.20 min.

Example 4 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-methanesulfonylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;(m/z): [M+H]⁺ calcd for C₂₅H₃₈N₆O₃S, 503.28; found 503.2. Retention time(anal. HPLC: 5-65% MeCN/H₂O over 4 min)=2.12 min.

Example 5 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-cyclohexylmethanesulfonylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;(m/z): [M+H]⁺ calcd for C₃₁H₄₈N₆O₃S, 585.35; found 585.4. Retention time(anal. HPLC: 5-75% MeCN/H₂O over 5 min)=2.67 min.

Example 6 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-methanesulfonylmethanesulfonylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;(m/z): [M+H]⁺ calcd for C₂₆H₄₀N₆O₅S₂, 581.26; found 581.2. Retentiontime (anal. HPLC: 5-75% MeCN/H₂O over 5 min)=2.22 min.

Example 7 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(3-(acetyl-methylamino)pyrrolidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;(m/z): [M+H]⁺ calcd for C₂₇H₄₀N₆O₂, 481.32; found 481.3. Retention time(anal. HPLC: 5-75% MeCN/H₂O over 5 min)=2.07 min.

Example 8 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(3-(acetylamino)pyrrolidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;(m/z): [M+H]⁺ calcd for C₂₆H₃₈N₆O₂, 467.31; found 467.4. Retention time(anal. HPLC: 5-75% MeCN/H₂O over 5 min)=1.89 min.

Example 9 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-((R)-3-(acetylamino)pyrrolidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;(m/z): [M+H]⁺ calcd for C₂₆H₃₈N₆O₂, 467.31; found 467.4. Retention time(anal. HPLC: 5-75% MeCN/H₂O over 5 min)=2.04 min.

Example 10 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-((S)-3-(acetylamino)pyrrolidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;(m/z): [M+H]⁺ calcd for C₂₆H₃₈N₆O₂, 467.31; found 467.4. Retention time(anal. HPLC: 5-75% MeCN/H₂O over 5 min)=2.07 min.

Example 11 1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[3-((S)-2-hydroxypropionylamino)pyrrolidin-1-yl]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;(m/z): [M+H]⁺ calcd for C₂₇H₄₀N₆O₃, 497.32; found 497.2. Retention time(anal. HPLC: 5-65% MeCN/H₂O over 5 min)=2.07 min.

Example 12 1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[(3S,4S)-3-(acetylmethylamino)-4-hydroxypyrrolidin-1-yl]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;(m/z): [M+H]⁺ calcd for C₂₇H₄₀N₆O₃, 497.32; found 497.2. Retention time(anal. HPLC: 5-65% MeCN/H₂O over 5 min)=2.15 min.

Example 13 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-((R)-3-ethanesulfonylaminopyrrolidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;(m/z): [M+H]⁺ calcd for C₂₆H₄₀N₆O₃S, 517.30; found 517.2. Retention time(anal. HPLC: 5-75% MeCN/H₂O over 5 min)=2.12 min.

Example 14 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-((R)-3-cyclohexylmethanesulfonylaminopyrrolidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;(m/z): [M+H]⁺ calcd for C₃₁H₄₈N₆O₃S, 585.36; found 585.4. Retention time(anal. HPLC: 5-75% MeCN/H₂O over min)=2.52 min.

Example 15 1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[3-(acetyl-methylamino)piperidin-1-yl]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;(m/z): [M+H]⁺ calcd for C₂₈H₄₂N₆O₂, 495.34; found 495.4. Retention time(anal. HPLC: 5-75% MeCN/H₂O over 5 min)=1.94 min.

Example 16 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(3-acetylaminopiperidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;(m/z): [M+H]⁺ calcd for C₂₇H₄₀N₆O₂, 481.33; found 481.2. Retention time(anal. HPLC: 5-75% MeCN/H₂O over 5 min)=2.01 min.

Example 17 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(3-methanesulfonylaminopiperidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;(m/z): [M+H]⁺ calcd for C₂₆H₄₀N₆O₃S, 517.30; found 517.4. Retention time(anal. HPLC: 5-75% MeCN/H₂O over 5 min)=1.97 min.

Example 18 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-((S)-3-methanesulfonylaminopiperidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;(m/z): [M+H]⁺ calcd for C₂₆H₄₀N₆O₃S, 517.30; found 517.4. Retention time(anal. HPLC: 5-75% MeCN/H₂O over 5 min)=1.99 min.

Example 19 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-((S)-3-ethanesulfonylaminopiperidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;(m/z): [M+H]⁺ calcd for C₂₇H₄₂N₆O₃S, 531.31; found 531.4. Retention time(anal. HPLC: 5-75% MeCN/H₂O over 5 min)=2.04 min.

Example 20 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-((S)-3-methanesulfonylmethanesulfonylaminopiperidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;(m/z): [M+H]⁺ calcd for C₂₇H₄₂N₆O₅S₂, 595.27; found 595.2. Retentiontime (anal. HPLC: 5-75% MeCN/H₂O over 5 min)=2.07 min.

EXAMPLE 21 Synthesis of 1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[(1-acetylpyrrolidin-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide

To a solution of 3-(methylamino)-1-acetylpyrrolidine (43 mg, 0.3 mmol)and N,N-diisopropylethylamine (12 μL, 0.3 mmol) in dichloromethane (1.5mL) was added sodium triacetoxyborohydride (128 mg, 0.6 mmol), and then1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-(2,2-dihydroxyethyl)-8-aza-bicyclo[3.2.1]oct-3-yl}amide(HCl salt) (78 mg, 0.2 mmol). The mixture was shaken at ambienttemperature for 15 min. After concentration under reduced pressure, thereaction mixture was dissolved in 50% aqueous acetic acid, and purifiedby preparative HPLC to provide the trifluroacetic acid salt of the titlecompound (56 mg, 99% purity). (m/z): [M+H]⁺ calcd for C₂₇H₄₀N₆O₂,481.33; found 481.2. Retention time (anal. HPLC: 5-65% MeCN/H₂O over 5min)=2.00 min.

EXAMPLES 22-30

Using processes similar to that of Example 21, except replacing the3-(methylamino)-1-acetylpyrrolidine with the appropriate secondaryamine, the compounds of Examples 22-30 were prepared.

Example 22 1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[((R)-1-acetylpyrrolidin-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;(m/z): [M+H]⁺ calcd for C₂₇H₄₀N₆O₂, 481.33; found 481.4. Retention time(anal. HPLC: 10-50% MeCN/H₂O over 5 min)=2.52 min.

Example 23 1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[((S)-1-acetylpyrrolidin-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;(m/z): [M+H]⁺ calcd for C₂₇H₄₀N₆O₂, 481.33; found 481.4. Retention time(anal. HPLC: 10-50% MeCN/H₂O over 5 min)=2.52 min.

Example 24 1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[(1-methanesulfonylpyrrolidin-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;(m/z): [M+H]⁺ calcd for C₂₆H₄₀N₆O₃S, 517.30; found 517.2. Retention time(anal. HPLC: 5-75% MeCN/H₂O over 5 min)=2.04 min.

Example 25 1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[((R)-1-methanesulfonylpyrrolidin-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;(m/z): [M+H]⁺ calcd for C₂₆H₄₀N₆O₃S, 517.30; found 517.2. Retention time(anal. HPLC: 5-65% MeCN/H₂O over 5 min)=2.20 min.

Example 26 1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[(1,1-dioxotetrahydro-1λ⁶-thiophen-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;(m/z): [M+H]⁺ calcd for C₂₅H₃₇N₅O₃S, 488.27; found 488.2. Retention time(anal. HPLC: 5-75% MeCN/H₂O over 5 min)=2.22 min.

Example 27 1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[(1,1-dioxotetrahydro-1λ⁶-thiophen-3-yl)-(2-hydroxyethyl)amino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;(m/z): [M+H]⁺ calcd for C₂₆H₃₉N₅O₄S, 518.28; found 518.2. Retention time(anal. HPLC: 5-65% MeCN/H₂O over 5 min)=2.25 min.

Example 28 1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[(1-acetyl-piperidin-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;(m/z): [M+H]⁺ calcd for C₂₆H₃₈N₆O₂, 495.34; found 495.4. Retention time(anal. HPLC: 5-75% MeCN/H₂O over 5 min)=1.95 min.

Example 29 1-isopropyl-1H-indazole-3-carboxylic acid ((1S,3R,5R)-8-{2-[(1,1-dioxohexahydro-1λ⁶-thiopyran-4-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;(m/z): [M+H]⁺ calcd for C₂₆H₃₉N₅O₃S, 502.29 found 502.2. Retention time(anal. HPLC: 5-65% MeCN/H₂O over 5 min)=2.12 min.

Example 30 1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[(1-methanesulfonylpiperidin-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;(m/z): [M+H]⁺ calcd for C₂₇H₄₂N₆O₃S, 531.31; found 531.4. Retention time(anal. HPLC: 5-75% MeCN/H₂O over 5 min)=2.07 min.

EXAMPLE 31 Synthesis of 5-fluoro-1-isopropyl-1H-indazole-3-carboxylicacid{(1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide

a. Preparation of 5-fluoro-1-isopropyl-1H-indazole-3-carboxylic acid

5-Fluoro-1H-indazole-3-carboxylic acid methyl ester was preparedaccording to the protocol described in (Buu-Hoi, N. P., et al. J.Hetereocyclic Chem. 1964, 1, 239-41. ¹H-NMR (DMSO-d₆): δ (ppm) 7.8 (dd,2H), 7.35 (dt, 1H), 3.8 (s, 3H). The methyl ester was alkylated at N¹with isopropyl iodide in the presence of potassium tert-butoxide inrefluxing THF. ¹H-NMR (CDCl₃): δ (ppm) 7.8 (dd, 1H), 7.6 (dd, 1H), 7.1(dt, 1H), 4.8 (hept, 1H), 1.6 (d, 6H). The isopropyl methyl ester wasthen hydrolyzed (1 M NaOH/THF, RT) to provide the title intermediate.

b. Preparation of 5-fluoro-1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-azabicyclo[3.2.1]oct-3-yl}amide

The title intermediate was prepared according to the procedure ofExample 1 parts e and f, using the intermediate of the previous step inplace of 1-isopropyl-1H-indazole-3-carboxylic acid. ¹H-NMR (DMSO-d₆): δ(ppm) 7.9 (br, 1H), 7.7 (dd, 1H), 7.6 (dd, 1H), 7.2 (dt, 1H), 4.9 (m,1H), 4.2 (br, 1H), 4.0 (br, 2H), 2.3-2.1 (br m, 8H), 1.5 (d, 6H). (m/z):[M+H]⁺ calcd for C₁₈H₂₃FN₄O, 331.19; found, 331.4. Retention time (anal.HPLC: 10-40% MeCN/H₂O over 6 min)=3.43 min.

c. Preparation of 5-fluoro-1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-(2,2-dimethoxyethyl)-8-aza-bicyclo[3.2.1]oct-3-yl}amide

The product of the previous step was reacted with dimethoxy acetaldehydeaccording to the process of Example 1 step g to provide the titleintermediate. (m/z): [M+H]⁺ calcd for C₂₂H₃₁FN₄O₃ 419.25; found, 419.3.

d. Preparation of 5-fluoro-1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-(2,2-dihydroxyethyl)-8-aza-bicyclo[3.2.1]oct-3-yl}amide

The intermediate of the previous step (1.0 g) was suspended in 10 mL of6 M hydrochloric acid and heated at 70° C. for 1 h. The reaction mixturewas cooled, and evaporated under reduced pressure to dryness to affordthe hydrochloric acid salt of the title intermediate. (m/z): [M+H]⁺calcd for C₂₀H₂₇FN₄O₃, 391.21; found, 391.4.

e. Synthesis of 5-fluoro-1-isopropyl-1H-indazole-3-carboxylic acid {(1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide

To a flask containing 40 mL of dichloromethane was added1-acetylpiperazine (613 mg; 4.78 mmol) and sodium triacetoxyborohydride(1.01 g). It was stirred for 5 min prior to addition of the product ofthe previous step (˜1 g). The final mixture was stirred for 1 h, atwhich the reaction was complete based on HPLC and mass spectrometricanalysis. Water (20 mL) was added slowly and the mixture was dilutedwith 300 mL of dichloromethane, and shaken in a funnel before collectingthe organic layer. It was washed with 1M NaOH (100 mL) and brine (100mL). Drying over MgSO₄, and evaporation afforded the title compoundwhich was purified by preparative HPLC to afford 380 mg of pure productas the TFA salt. ¹H-NMR (DMSO-d₆; free base): δ (ppm) 8.0 (br, 1H), 7.8(dd, 1H), 7.6 (dd, 1H), 7.23 (dt, 1H), 5.0 (hept, 1H), 4.0-3.9 (br, 3H),3.5 (br, 2H), 3.2-2.8 (br, 10H), 2.2 (br m, 8H), 1.9 (s, 3H), 1.4 (d,6H). (m/z): [M+H]⁺ calcd for C₂₆H₃₇FN₆O₂, 485.30; found, 485.5.Retention time (anal. HPLC: 10-70% MeCN/H₂O over 6 min)=2.28 min.

EXAMPLE 32 Synthesis of 1-propyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide

a. Preparation of 1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide

The title intermediate was prepared according to the procedure ofExample 1 using 1H-indazole-3-carboxylic acid in place of1-isopropyl-1H-indazole-3-carboxylic acid in step e. (m/z): [M+H]⁺ calcdfor C₂₃H₃₂N₆O₂, 425.27; found, 425.4. Retention time (anal. HPLC: 10-40%MeCN/H₂O over 6 min)=1.47 min.

b. Alternative synthesis of 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide

To a solution of anhydrous DMF (2 mL) containing the TFA salt of theintermediate of the previous step (80 mg, 0.123 mmol) was addedpotassium tert-butoxide (48 mg, 0.43 mmol) and isopropyl iodide (37 μL,0.368 mmol). The mixture was shaken at 85° C. for 12 h, and thenevaporated to dryness, affording pale brown residue, which was dissolvedin 50% aq. acetic acid, and fractionated by preparative HPLC to affordthe title compound. (m/z): [M+H]⁺ calcd for C₂₆H₃₈N₆O₂, 467.31; obsd.467.2 [M+H]⁺. Retention time (anal. HPLC: 5-65% MeCN/H₂O over 6min)=2.09 min.

c. Synthesis of 1-propyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amideUsing a process similar to that of step b, except replacing theisopropyl iodide with n-propyl iodide, the title compound was prepared.(m/z): [M+H]⁺ calcd for C₂₆H₃₈N₆O₂, calcd. 467.31; obsd. 467.4 [M+H]⁺.Retention time (anal. HPLC: 5-65% MeCN/H₂O over 6 min)=2.05 min.

EXAMPLES 33-35

Using processes similar to that of Example 32, except replacing theisopropyl iodide with the appropriate alkyl halide, the compounds ofExamples 33-35 were prepared.

Example 33 1-butyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;(m/z): [M+H]⁺ calcd for C₂₇H₄₀N₆O₂, 481.33; found 481.4. Retention time(anal. HPLC: 5-65% MeCN/H₂O over 6 min)=2.26 min.

Example 34 1-cyclobutyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;(m/z): [M+H]⁺ calcd for C₂₇H₃₈N₆O₂, 479.31; found 479.4. Retention time(anal. HPLC: 5-65% MeCN/H₂O over 6 min)=2.20 min.

Example 35 1-cyclopentyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;(m/z): [M+H]⁺ calcd for C₂₈H₄₀N₆O₂, 493.33; found 493.2. Retention time(anal. HPLC: 5-65% MeCN/H₂O over 6 min)=2.34 min.

EXAMPLES 36-40

Using processes similar to those described above, the compounds ofExamples 36-40 can be prepared.

Example 36 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-((R)-3-(acetylmethylamino)pyrrolidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide.

Example 37 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-((S)-3-(acetylmethylamino)pyrrolidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide.

Example 38 1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[((S)-1-methanesulfonylpyrrolidin-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide.

Example 39 1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[(R)-(1,1-dioxo-tetrahydro-1λ⁶-thiophen-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide.

Example 40 1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[(S)-(1,1-dioxo-tetrahydro-1λ⁶-thiophen-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide.

EXAMPLE 41 Synthesis of 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amidedihydrochloride

a. Preparation of(1S,3R,5R)-3-[1-isopropyl-1H-indazole-3-carbonyl)amino]-8-azabicyclo[3.2.1]octane-8-carboxylicacid tert-butyl ester

A 5 L three-necked round bottom flask equipped with a magnetic stir bar,a reflux condenser, an addition funnel, a nitrogen inlet and athermometer was charged with 1-isopropyl-1H-indazole-3-carboxylic acid(250 g, 1.224 mol, 1.1 eq) and 2.5 L of toluene. The resultingsuspension was stirred and heated at 70-80° C. To this suspension wasadded thionyl chloride (218.4 g, 1.836 mol, 1.65 eq) over a period of 40min. The mixture was heated at 90-100° C. for 1 h and was cooled to 25°C.

A separate 12 L three-necked round bottom flask equipped with amechanical stirrer, an addition funnel, a nitrogen inlet and athermometer was charged with 2.5 L of toluene and 3 N NaOH (preparedfrom diluting 356 g of 50% NaOH with water to 1.48 L), and(1S,3R,5R)-3-amino-8-azabicyclo[3.2.1]octane-8-carboxylic acidtert-butyl ester (251.9 g, 1.113 mol, 1 eq). The resulting suspensionwas stirred at 23° C. for 10 min and was cooled to 5° C. To thissuspension was added the acid chloride solution in toluene over a periodof 90 min keeping the internal temperature at ˜5° C. throughout theaddition period. The mixture was stirred for 30 min. The reaction waswarmed to 25° C.; the aqueous layer was discarded (1.58 L, pH>13). Theorganic layer was washed with 1 L of 20 wt % brine; and the aqueouslayer was discarded (1.005 L, ˜pH 8). The organic layer was collected(5.3 L) and was concentrated to half of the volume (˜2.6 L), and wasused in the following step without purification

b. Preparation of 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-aza-bicyclo[3.2.1]oct-3-yl}amide

A 12 L three-necked round bottom flask equipped with a mechanicalstirrer, an addition funnel, a nitrogen inlet and a thermometer wascharged with the product of the previous step. To this solution wasadded trifluoroacetic acid (0.65 L) over a period of 10 min. Theresulting mixture was stirred for 1 h at ambient temperature.

Water (3.3 L) was added to the reaction mixture. The resultingsuspension was stirred at 23° C. for 10 min and was allowed to settle togive a three-layer mixture. The top two layers were discarded and thebottom layer (820 mL) was collected and added to MTBE (6560 mL) over aperiod of 90 min. The resulting suspension was cooled to 5° C. and wasagitated for 1 h. The suspension was filtered; the wet cake was washedwith MTBE (500 mL), and dried under reduced pressure (80 mm Hg) for 60 hto give the title intermediate (386 g, 81% yield, 99.2% purity by HPLC)as an off-white sandy solid.

c. Preparation of 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-(2,2-dimethoxyethyl)-8-aza-bicyclo[3.2.1]oct-3-yl}amide

A 3 L three-necked round bottom flask equipped with a magnetic stirrer,a nitrogen inlet and a thermometer was charged with the intermediate ofthe previous step (84 g, 0.197 mol), dichloromethane (840 mL), andsodium triacetoxyborohydride (62.6 g, 0.295 mol). The resultingsuspension was stirred for 10 min, cooled to 10° C. and 60 wt % aqueousdimethoxyacetaldehyde (51.3 g, 0.295 mol) was added. This solution wasstirred for 30 min, warmed to 25° C., and stirred for 1 h. The mixturewas filtered through Celite, washed with dichloromethane (150 mL) andthen with 5 wt % brine solution (400 g). The aqueous and organic layerswere separated and the organic layer was concentrated to a dark oil(˜150 mL), which was used in the following step without purification.

d. Preparation of 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-(2.2-dihydroxyethyl)-8-aza-bicyclo[3.2.1]oct-3-yl}amide

A 1 L three-necked round bottom flask equipped with a magnetic stirrer,a nitrogen inlet and a thermometer was charged with the product of theprevious step and water (250 mL) and heated to 50-55° C. To thissolution was added 3N HCl (82 mL, 0.985 mol). The resulting mixture wasstirred at 75° C. for 1 h. The reaction mixture was cooled to 25° C. andneutralized with 25 wt % NaOH (159 g, 0.99 mol) to pH 3.51. After about20 min, the lower layer was collected (˜120 mL) to provide the titleintermediate, which was used in the following step without purification.

e. Synthesis of 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amidedihydrochloride

A 3 L three-necked round bottom flask equipped with a magnetic stirrer,a nitrogen inlet and a thermometer was charged with sodiumtriacetoxyborohydride (84 g, 0.349 mol) and dichloromethane (800 mL).The resulting mixture was stirred at 25° C. and charged with1-acetylpiperazine (51 g, 0.394 mol). The addition assembly was rinsedwith dichloromethane (20 mL). The mixture was stirred for 5 min andcharged with the product of the previous step (˜120 mL) in 15 minmaintaining the internal temperature less than 25° C. The mixture wasstirred for 15 min, filtered through Celite and washed withdichloromethane (2×100 mL). The filtrate was washed with 1N NaOH (500mL). The layers were separated and the lower organic layer was collectedand concentrated to ˜150 mL.

Absolute ethanol (250 mL) was added and the mixture was concentrated to˜200 mL. To this mixture, absolute ethanol (800 mL) was added and themixture was heated to 40° C. To this mixture, 3 N HCl (33 mL, 0.396 mol)was added in 3 min. The mixture was stirred for 10 min andcrystallization began. The resulting suspension was stirred at 55° C.for 2 h and cooled to 25° C. The mixture was filtered though Whatman #2filter paper and the wet cake was washed with absolute ethanol (2×100mL). The product was dried under nitrogen for 30 min and then undervacuum at 40-50° C. for 24 h to provide the title compound (82 g).

EXAMPLE 42 Synthesis of 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amidedihydrobromide

A 500 mL three-necked round bottom flask equipped with a magneticstirrer, a nitrogen inlet and a thermometer was charged with water (120mL) and 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amidedihydrochloride (12 g, 22.2 mmol). The resulting mixture was stirred togive a light yellow clear solution. To this solution was added 25 wt %NaOH (7.83 g, 24.4 mmol) in 2 min to give a white milky suspension.Dichloromethane (120 mL) was added and the mixture was stirred for 30min to give a clear two-layer solution. The layers were separated togive an aqueous layer (113 mL) and an organic layer (125 mL), which waswashed with 10% aqueous NaBr (120 mL). The layers were separated to givean organic layer (120 mL) which was concentrated to about one-quartervolume. Absolute ethanol (250 mL) was added and the mixture wasdistilled to give ˜200 mL total volume. The solution was stirred at 58°C. and 48 wt % aqueous HBr (8.2 g, 49 mmol) was added in 2 min.Precipitation was observed when more than half of the HBr was added. Themixture was stirred at 55° C. to 62° C. for 1 h and then cooled toambient temperature and filtered. The filtrate was washed with absoluteethanol (40 mL), dried under nitrogen for 20 min and dried at 45° C.under vacuum for 48 h to give the title compound (13.42 g) as a whitesolid.

EXAMPLE 43 Synthesis of Fumaric Acid Salt of1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide

To a solution of 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide(0.1 g, 0.21 mmol) in 50% acetonitrile/water (1 mL) was added anethanolic 1M fumaric acid solution (0.44 mL 0.42 mmol). The resultingsolution was lyophilized overnight and then mixed with ethyl acetate (1mL). Hot ethanol was added to this mixture with heating until ahomogeneous solution was obtained (0.4 mL). The resulting clear solutionwas then allowed to crystallize at room temperature. The resulting solidwas filtered, washed with ethanol, and dried under vacuum to give thetitle compound as a solid (0.13 g).

EXAMPLE 44 Synthesis of Phosphoric Acid Salt of1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide

To a solution of 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide(0.2 g, 0.43 mmol) in methanol (3 mL) was added an ethanolic 1Mphosphoric acid solution (0.43 mL, 0.43 mmol). The resultingheterogeneous solution was then heated to solubilize, filtered, andallowed to cool overnight. The resulting solid was filtered, washed withmethanol and dried under vacuum to give the title compound as a solid(0.08 g).

EXAMPLE 45 Synthesis of p-toluene Sulfonic Acid Salt of1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide

A solution of 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide(38.7 mg, 0.08 mmol) in isopropanol (2 mL) was heated in a 75° C. waterbath and solid p-toluenesulfonic acid monohydrate (32.3 mg, 0.17 mmol)was added. The resulting solution was heated until the solids dissolvedand then allowed to cool to room temperature. Crystals of the titlecompound formed overnight.

EXAMPLE 46 Synthesis of Acid Salts of1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide

Using procedures similar to those of Examples 43-45, the following acidsalts of 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amidewere prepared in solid form using the number of equivalents of acidindicated in parentheses: acetate (2); benzoate (2); nitrate (2);propionate (1); tartrate (2); phosphate (0.5).

EXAMPLE 47 Radioligand Binding Assay on 5-HT₄(C) Human Receptors

a. Membrane Preparation 5-HT_(4(c))

HEK-293 (human embryonic kidney) cells stably-transfected with human5-HT_(4(c)) receptor cDNA (Bmax=˜6.0 pmol/mg protein, as determinedusing [³H]-GR113808 membrane radioligand binding assay) were grown inT-225 flasks in Dulbecco's Modified Eagles Medium (DMEM) containing4,500 mg/L D-glucose and pyridoxine hydrochloride (GIBCO-InvitrogenCorp., Carlsbad Calif.: Cat #11965) supplemented with 10% fetal bovineserum (FBS) (GIBCO-Invitrogen Corp.: Cat #10437), 2 mM L-glutamine and(100 units) penicillin-(100 μg) streptomycin/ml (GIBCO-Invitrogen Corp.:Cat #15140) in a 5% CO₂, humidified incubator at 37° C. Cells were grownunder continuous selection pressure by the addition of 800 μg/mLgeneticin (GIBCO-Invitrogen Corp.: Cat #10131) to the medium.

Cells were grown to roughly 60-80% confluency (<35 subculture passages).At 20-22 hours prior to harvesting, cells were washed twice and fed withserum-free DMEM. All steps of the membrane preparation were performed onice. The cell monolayer was lifted by gentle mechanical agitation andtrituration with a 25 mL pipette. Cells were collected by centrifugationat 1000 rpm (5 min).

For the membrane preparation, cell pellets were resuspended in ice-cold50 mM 4-(2-hydroxyethyl)-1-piperazineethanesulphonic acid (HEPES), pH7.4 (membrane preparation buffer) (40 mL/total cell yield from 30-40T225 flasks) and homogenized using a polytron disrupter (setting 19,2×10 s) on ice. The resultant homogenates were centrifuged at 1200 g for5 min at 4° C. The pellet was discarded and the supernatant centrifugedat 40,000 g (20 min). The pellet was washed once by resuspension withmembrane preparation buffer and centrifugation at 40,000 g (20 min). Thefinal pellet was resuspended in 50 mM HEPES, pH 7.4 (assay buffer)(equivalent 1 T225 flask/1 mL). Protein concentration of the membranesuspension was determined by the method of Bradford (Bradford, 1976).Membranes were stored frozen in aliquots at −80° C.

b. Radioligand Binding Assays

Radioligand binding assays were performed in 1.1 mL 96-deep wellpolypropylene assay plates (Axygen) in a total assay volume of 400 μLcontaining 2 μg membrane protein in 50 mM HEPES pH 7.4, containing0.025% bovine serum albumin (BSA). Saturation binding studies fordetermination of K_(d) values of the radioligand were performed using[³H]-GR113808 (Amersham Inc., Bucks, UK: Cat #TRK944; specific activity˜82 Ci/mmol) at 8-12 different concentrations ranging from 0.001 nM-5.0nM. Displacement assays for determination of pK_(i) values of compoundswere performed with [³H]-GR113808 at 0.15 nM and eleven differentconcentrations of compound ranging from 10 pM-100 μM.

Test compounds were received as 10 mM stock solutions in DMSO anddiluted to 400 μM into 50 mM HEPES pH 7.4 at 25° C., containing 0.1%BSA, and serial dilutions (1:5) then made in the same buffer.Non-specific binding was determined in the presence of 1 μM unlabeledGR113808. Assays were incubated for 60 min at room temperature, and thenthe binding reactions were terminated by rapid filtration over 96-wellGF/B glass fiber filter plates (Packard BioScience Co., Meriden, Conn.)presoaked in 0.3% polyethyleneimine. Filter plates were washed threetimes with filtration buffer (ice-cold 50 mM HEPES, pH7.4) to removeunbound radioactivity. Plates were dried, 35 μL Microscint-20 liquidscintillation fluid (Packard BioScience Co., Meriden, Conn.) was addedto each well and plates were counted in a Packard Topcount liquidscintillation counter (Packard BioScience Co., Meriden, Conn.).

Binding data were analyzed by nonlinear regression analysis with theGraphPad Prism Software package (GraphPad Software, Inc., San Diego,Calif.) using the 3-parameter model for one-site competition. The BOTTOM(curve minimum) was fixed to the value for nonspecific binding, asdetermined in the presence of 1 μM GR113808. K_(i) values for testcompounds were calculated, in Prism, from the best-fit IC₅₀ values, andthe K_(d) value of the radioligand, using the Cheng-Prusoff equation(Cheng and Prusoff, Biochemical Pharmacology, 1973, 22, 3099-108):K_(i)=IC₅₀/(1+[L]/K_(d)) where [L]=concentration [³H]-GR113808. Resultsare expressed as the negative decadic logarithm of the K_(i) values,pK_(i).

Test compounds having a higher pK_(i) value in this assay have a higherbinding affinity for the 5-HT₄ receptor. The compounds of the inventionwhich were tested in this assay had a pK_(i) value ranging from about6.3 to about 9.0, typically ranging from about 7.0 to about 8.6.

EXAMPLE 48 Radioligand Binding Assay on 5-HT_(3A) Human Receptors:Determination of Receptor Subtype Selectivity

a. Membrane Preparation 5-HT_(3A)

HEK-293 (human embryonic kidney) cells stably-transfected with human5-HT_(3A) receptor cDNA were obtained from Dr. Michael Bruess(University of Bonn, GDR) (Bmax=˜9.0 pmol/mg protein, as determinedusing [³H]-GR65630 membrane radioligand binding assay). Cells were grownin T-225 flasks or cell factories in 50% Dulbecco's Modified EaglesMedium (DMEM) (GIBCO-Invitrogen Corp., Carlsbad, Calif.: Cat #11965) and50% Ham's F12 (GIBCO-Invitrogen Corp.: Cat #11765) supplemented with 10%heat inactivated fetal bovine serum (FBS) (Hyclone, Logan, Utah: Cat#SH30070.03) and (50 units) penicillin-(50 μg) streptomycin/ml(GIBCO-Invitrogen Corp.: Cat #15140) in a 5% CO₂, humidified incubatorat 37° C.

Cells were grown to roughly 70-80% confluency (<35 subculture passages).All steps of the membrane preparation were performed on ice. To harvestthe cells, the media was aspirated and cells were rinsed with Ca²⁺,Mg²⁺-free Dulbecco's phosphate buffered saline (dPBS). The cellmonolayer was lifted by gentle mechanical agitation. Cells werecollected by centrifugation at 1000 rpm (5 min). Subsequent steps of themembrane preparation followed the protocol described above for themembranes expressing 5-HT_(4(c)) receptors.

b. Radioligand Binding Assays

Radioligand binding assays were performed in 96-well polypropylene assayplates in a total assay volume of 200 μL containing 1.5-2 μg membraneprotein in 50 mM HEPES pH 7.4, containing 0.025% BSA assay buffer.Saturation binding studies for determination of K_(d) values of theradioligand were performed using [³H]-GR65630 (PerkinElmer Life SciencesInc., Boston, Mass.: Cat #NET1011, specific activity ˜85 Ci/mmol) attwelve different concentrations ranging from 0.005 nM to 20 nM.Displacement assays for determination of pK_(i) values of compounds wereperformed with [³H]-GR65630 at 0.50 nM and eleven differentconcentrations of compound ranging from 10 pM to 100 μM. Compounds werereceived as 10 mM stock solutions in DMSO (see section 3.1), diluted to400 μM into 50 mM HEPES pH 7.4 at 25° C., containing 0.1% BSA, andserial (1:5) dilutions then made in the same buffer. Non-specificbinding was determined in the presence of 10 μM unlabeled MDL72222.Assays were incubated for 60 min at room temperature, then the bindingreactions were terminated by rapid filtration over 96-well GF/B glassfiber filter plates (Packard BioScience Co., Meriden, Conn.) presoakedin 0.3% polyethyleneimine. Filter plates were washed three times withfiltration buffer (ice-cold 50 mM HEPES, pH7.4) to remove unboundradioactivity. Plates were dried, 35 μL Microscint-20 liquidscintillation fluid (Packard BioScience Co., Meriden, Conn.) was addedto each well and plates were counted in a Packard Topcount liquidscintillation counter (Packard BioScience Co., Meriden, Conn.).

Binding data were analyzed using the non-linear regression proceduredescribed above to determine K_(i) values. The BOTTOM (curve minimum)was fixed to the value for nonspecific binding, as determined in thepresence of 10 μM MDL72222. The quantity [L] in the Cheng-Prusoffequation was defined as the concentration [³H]-GR65630.

Selectivity for the 5-HT₄ receptor subtype with respect to the 5-HT₃receptor subtype was calculated as the ratioK_(i)(5-HT_(3A))/K_(i)(5-HT_(4(c))). The compounds of the inventionwhich were tested in this assay had a 5-HT₄/5-HT₃ receptor subtypeselectivity ranging from about 25 to about 4000, typically ranging fromabout 100 to about 4000.

EXAMPLE 49 Whole-Cell cAMP Accumulation Flashplate Assay with HEK-293Cells Expressing Human 5-HT_(4(c)) Receptors

In this assay, the functional potency of a test compound was determinedby measuring the amount of cyclic AMP produced when HEK-293 cellsexpressing 5-HT₄ receptors were contacted with different concentrationsof test compound.

a. Cell Culture

HEK-293 (human embryonic kidney) cells stably-transfected with clonedhuman 5-HT_(4(c)) receptor cDNA were prepared expressing the receptor attwo different densities: (1) at a density of about 0.5-0.6 pmol/mgprotein, as determined using a [³H]-GR113808 membrane radioligandbinding assay, and (2) at a density of about 6.0 pmol/mg protein. Thecells were grown in T-225 flasks in Dulbecco's Modified Eagles Medium(DMEM) containing 4,500 mg/L D-glucose (GIBCO-Invitrogen Corp.: Cat#11965) supplemented with 10% fetal bovine serum (FBS) (GIBCO-InvitrogenCorp.: Cat #10437) and (100 units) penicillin-(100 μg) streptomycin/ml(GIBCO-Invitrogen Corp.: Cat #15140) in a 5% CO₂, humidified incubatorat 37° C. Cells were grown under continuous selection pressure by theaddition of geneticin (800 μg/mL: GIBCO-Invitrogen Corp.: Cat #10131) tothe medium.

b. Cell Preparation

Cells were grown to roughly 60-80% confluency. Twenty to twenty-twohours prior to assay, cells were washed twice, and fed, with serum-freeDMEM containing 4,500 mg/L D-glucose (GIBCO-Invitrogen Corp.: Cat#11965). To harvest the cells, the media was aspirated and 10 mL Versene(GIBCO-Invitrogen Corp.: Cat #15040) was added to each T-225 flask.Cells were incubated for 5 min at RT and then dislodged from the flaskby mechanical agitation. The cell suspension was transferred to acentrifuge tube containing an equal volume of pre-warmed (37° C.) dPBSand centrifuged for 5 min at 1000 rpm. The supernatant was discarded andthe pellet was re-suspended in pre-warmed (37° C.) stimulation buffer(10 mL equivalent per 2-3 T-225 flasks). This time was noted and markedas time zero. The cells were counted with a Coulter counter (count above8 μm, flask yield was 1-2×10⁷ cells/flask). Cells were resuspended at aconcentration of 5×10⁵ cells/ml in pre-warmed (37° C.) stimulationbuffer (as provided in the flashplate kit) and preincubated at 37° C.for 10 min.

cAMP assays were performed in a radioimmunoassay format using theFlashplate Adenylyl Cyclase Activation Assay System with ¹²⁵I-cAMP(SMP004B, PerkinElmer Life Sciences Inc., Boston, Mass.), according tothe manufacturer's instructions.

Cells were grown and prepared as described above. Final cellconcentrations in the assay were 25×10³ cells/well and the final assayvolume was 100 μL. Test compounds were received as 10 mM stock solutionsin DMSO, diluted to 400 μM into 50 mM HEPES pH 7.4 at 25° C., containing0.1% BSA, and serial (1:5) dilutions then made in the same buffer.Cyclic AMP accumulation assays were performed with 11 differentconcentrations of compound ranging from 10 pM to 100 μM (final assayconcentrations). A 5-HT concentration-response curve (10 pM to 100 μM)was included on every plate. The cells were incubated, with shaking, at37° C. for 15 min and the reaction terminated by addition of 100 μl ofice-cold detection buffer (as provided in the flashplate kit) to eachwell. The plates were sealed and incubated at 4° C. overnight. Boundradioactivity was quantified by scintillation proximity spectroscopyusing the Topcount (Packard BioScience Co., Meriden, Conn.).

The amount of cAMP produced per mL of reaction was extrapolated from thecAMP standard curve, according to the instructions provided in themanufacturer's user manual. Data were analyzed by nonlinear regressionanalysis with the GraphPad Prism Software package using the 3-parametersigmoidal dose-response model (slope constrained to unity). Potency dataare reported as pEC₅₀ values, the negative decadic logarithm of the EC₅₀value, where EC₅₀ is the effective concentration for a 50% maximalresponse.

Test compounds exhibiting a higher pEC₅₀ value in this assay have ahigher potency for agonizing the 5-HT₄ receptor. The compounds of theinvention which were tested in this assay, for example, in the cell line(1) having a density of about 0.5-0.6 pmol/mg protein, had a pEC₅₀ valueranging from about 6.3 to about 9.0, typically ranging from about 7.5 toabout 8.5.

EXAMPLE 50 In Vitro Voltage Clamp Assay of Inhibition of Potassium IonCurrent in Whole Cells Expressing the hERG Cardiac Potassium Channel

CHO-K1 cells stably transfected with hERG cDNA were obtained from GailRobertson at the University of Wisconsin. Cells were held in cryogenicstorage until needed. Cells were expanded and passaged in Dulbecco'sModified Eagles Medium/F12 supplemented with 10% fetal bovine serum and200 μg/mL geneticin. Cells were seeded onto poly-D-lysine (100 μg/mL)coated glass coverslips, in 35 mm² dishes (containing 2 mL medium) at adensity that enabled isolated cells to be selected for whole cellvoltage-clamp studies. The dishes were maintained in a humidified, 5%CO₂ environment at 37° C.

Extracellular solution was prepared at least every 7 days and stored at4° C. when not in use. The extracellular solution contained (mM): NaCl(137), KCl (4), CaCl₂ (1.8), MgCl₂ (1), Glucose (10),4-(2-hydroxyethyl)-1-piperazineethanesulphonic acid (HEPES) (10), pH 7.4with NaOH. The extracellular solution, in the absence or presence oftest compound, was contained in reservoirs, from which it flowed intothe recording chamber at approximately 0.5 mL/min. The intracellularsolution was prepared, aliquoted and stored at −20° C. until the day ofuse. The intracellular solution contained (mM): KCl (130), MgCl₂ (1),ethylene glycol-bis(beta-aminoethyl ether) N,N,N′,N′-tetra acetic acidsalt (EGTA) (5), MgATP (5),4-(2-hydroxyethyl)-1-piperazineethanesulphonic acid (HEPES) (10), pH 7.2with KOH. All experiments were performed at room temperature (20-22°C.).

The coverslips on which the cells were seeded were transferred to arecording chamber and perfused continuously. Gigaohm seals were formedbetween the cell and the patch electrode. Once a stable patch wasachieved, recording commenced in the voltage clamp mode, with theinitial holding potential at −80 mV. After a stable whole-cell currentwas achieved, the cells were exposed to test compound. The standardvoltage protocol was: step from the holding potential of −80 mV to +20mV for 4.8 sec, repolarize to −50 mV for 5 sec and then return to theoriginal holding potential (−80 mV). This voltage protocol was run onceevery 15 sec (0.067 Hz). Peak current amplitudes during therepolarization phase were determined using pClamp software. Testcompounds at a concentration of 3 μM were perfused over the cells for 5minutes, followed by a 5-minute washout period in the absence ofcompound. Finally a positive control (cisapride, 20 nM) was added to theperfusate to test the function of the cell. The step from −80 mV to +20mV activates the hERG channel, resulting in an outward current. The stepback to −50 mV results in an outward tail current, as the channelrecovers from inactivation and deactivates.

Peak current amplitudes during the repolarization phase were determinedusing pCLAMP software. The control and test article data were exportedto Origin® (OriginLab Corp., Northampton Mass.) where the individualcurrent amplitudes were normalized to the initial current amplitude inthe absence of compound. The normalized current means and standarderrors for each condition were calculated and plotted versus the timecourse of the experiment.

Comparisons were made between the observed K⁺ current inhibitions afterthe five-minute exposure to either the test article or vehicle control(usually 0.3% DMSO). Statistical comparisons between experimental groupswere performed using a two-population, independent t-test (MicrocalOrigin v. 6.0). Differences were considered significant at p<0.05.

The smaller the percentage inhibition of the potassium ion current inthis assay, the smaller the potential for test compounds to change thepattern of cardiac repolarization when used as therapeutic agents. Thecompounds of the invention which were tested in this assay at aconcentration of 3 μM exhibited an inhibition of the potassium ioncurrent of less than about 20%, typically, less than about 15%.

EXAMPLE 51 In Vitro Model of Oral Bioavailability: Caco-2 PermeationAssay

The Caco-2 permeation assay was performed to model the ability of testcompounds to pass through the intestine and get into the blood streamafter oral administration. The rate at which test compounds in solutionpermeate a cell monolayer designed to mimic the tight junction of humansmall intestinal monolayers was determined.

Caco-2 (colon, adenocarcinoma; human) cells were obtained from ATCC(American Type Culture Collection; Rockville, Md.). For the permeationstudy, cells were seeded at a density of 63,000 cells/cm on pre-wettedtranswells polycarbonate filters (Costar; Cambridge, Mass.). A cellmonolayer was formed after 21 days in culture. Following cell culture inthe transwell plate, the membrane containing the cell monolayer wasdetached from the transwell plate and inserted into the diffusionchamber (Costar; Cambridge, Mass.). The diffusion chamber was insertedinto the heating block which was equipped with circulating external,thermostatically regulated 37° C. water for temperature control. The airmanifold delivered 95% O₂/5% CO₂ to each half of a diffusion chamber andcreated a laminar flow pattern across the cell monolayer, which waseffective in reducing the unstirred boundary layer.

The permeation study was performed with test compound concentrations at100 μM and with ¹⁴C-mannitol to monitor the integrity of the monolayer.All experiments were conducted at 37° C. for 60 min. Samples were takenat 0, 30 and 60 min from both the donor and receiver sides of thechamber. Samples were analyzed by HPLC or liquid scintillation countingfor test compound and mannitol concentrations. The permeationcoefficient (K_(p)) in cm/sec was calculated.

In this assay, a K_(p) value greater than about 10×10⁻⁶ cm/sec isconsidered indicative of favorable bioavailability. The compounds of theinvention that were tested in this assay exhibited K_(p) values ofbetween about 15×10⁻⁶ cm/sec and about 50×10⁻⁶ cm/sec, typically betweenabout 20×10⁻⁶ cm/sec and about 40×10⁻⁶ cm/sec.

EXAMPLE 52 Pharmacokinetic Study in the Rat

Aqueous solution formulations of test compounds were prepared in 0.1%lactic acid at a pH of between about 5 and about 6. Male Sprague-Dawleyrats (CD strain, Charles River Laboratories, Wilmington, Mass.) weredosed with test compounds via intravenous administration (IV) at a doseof 2.5 mg/kg or by oral gavage (PO) at a dose of 5 mg/kg. The dosingvolume was 1 mL/kg for IV and 2 mL/kg for PO administration. Serialblood samples were collected from animals pre-dose, and at 2 (IV only),5, 15, and 30 min, and at 1, 2, 4, 8, and 24 hours post-dose.Concentrations of test compounds in blood plasma were determined byliquid chromatography-mass spectrometry analysis (LC-MS/MS) (MDS SCIEX,API 4000, Applied Biosystems, Foster City, Calif.) with a lower limit ofquantitation of 1 ng/mL.

Standard pharmacokinetic parameters were assessed by non-compartmentalanalysis (Model 201 for IV and Model 200 for PO) using WinNonlin(Version 4.0.1, Pharsight, Mountain View, Calif.). The maximum in thecurve of test compound concentration in blood plasma vs. time is denotedC_(max). The area under the concentration vs. time curve from the timeof dosing to the last measurable concentration (AUC(0-t)) was calculatedby the linear trapezoidal rule. Oral bioavailability (F(%)), i.e. thedose-normalized ratio of AUC(0-t) for PO administration to AUC(0-t) forIV administration, was calculated as:F(%)=AUC _(PO) /AUC _(IV)×Dose_(IV)/Dose_(PO)×100%

Test compounds which exhibit larger values of the parameters C_(max),AUC(0-t), and F(%) in this assay are expected to have greaterbioavailability when administered orally. The compounds of the inventionthat were tested in this assay had C_(max) values ranging from about0.05 to about 0.35 μg/mL, typically ranging from about 0.1 to about 0.35μg/mL and AUC(0-t) values ranging from about 0.15 to about 0.8 μg-hr/mL,typically ranging from about 0.25 to about 0.8 μg·hr/mL. By way ofexample, the compound of Example 1 had a C_(max) value of 0.25 μg/mL, anAUC(0-t) value of 0.73 μg-hr/mL and oral bioavailability (F(%)) in therat model of about 100%.

While the present invention has been described with reference to thespecific embodiments thereof, it should be understood by those skilledin the art that various changes may be made and equivalents may besubstituted without departing from the true spirit and scope of theinvention. In addition, many modifications may be made to adapt aparticular situation, material, composition of matter, process, processstep or steps, to the objective, spirit and scope of the presentinvention. All such modifications are intended to be within the scope ofthe claims appended hereto. Additionally, all publications, patents, andpatent documents cited hereinabove are incorporated by reference hereinin full, as though individually incorporated by reference.

1. A compound of formula (I):

wherein: R¹ is hydrogen, halo, hydroxy, C₁₋₄alkyl, or C₁₋₄alkoxy; R² isC₃₋₄alkyl, or C₃₋₆cycloalkyl; and W is selected from: (i) a group offormula (II):

wherein X is: NC(O)R^(a), wherein R^(a) is C₁₋₃alkyl ortetrahydrofuranyl, wherein C₁₋₃ alkyl is optionally substituted with —OHor C₁₋₃alkoxy; S(O)₂; or NS(O)₂R^(b), wherein R^(b) is methyl,optionally substituted with —OH, C₁₋₃alkoxy, C₅₋₆cycloalkyl, or—S(O)₂—C₁₋₃alkyl; (ii) a group of formula (II):

wherein: R^(y) is —OH or C₁₋₃alkoxy; p is 0 or 1; n is 1 or 2; and Y is:NR^(c)C(O)R^(d), wherein R^(c) is hydrogen or C₁₋₃alkyl and R^(d) isC₁₋₃alkyl optionally substituted with —OH or C₁₋₃alkoxy, orNR^(e)S(O)₂R^(f), wherein R^(e) is hydrogen and R^(f) is C₁₋₃alkyl,optionally substituted with —OH, C₁₋₃alkoxy, C₅₋₆cycloalkyl, or—S(O)₂—C₁₋₃alkyl; and (iii) a group of formula (IV):

wherein: R^(z) is hydrogen, C₁₋₃alkyl, or C₂₋₃alkyl substituted with —OHor C₁₋₃alkoxy; m is 1 or 2; q is 1 or 2, provided that the sum of m andq is not equal to 4; and Z is: NC(O)R^(g), wherein R^(g) is C₁₋₃alkyl,optionally substituted with —OH or C₁₋₃alkoxy, S(O)₂; or NS(O)₂R^(h),wherein R^(h) is methyl, optionally substituted with —OH, C₁₋₃alkoxy,C₅₋₆cycloalkyl, or —S(O)₂—C₁₋₃alkyl; or a pharmaceutically-acceptablesalt or solvate or stereoisomer thereof.
 2. The compound of claim 1wherein R¹ is hydrogen or halo.
 3. The compound of claim 1 wherein R² isisopropyl or C₄₋₅cycloalkyl.
 4. The compound of claim 1 wherein W is agroup of formula (II).
 5. The compound of claim 4 wherein R^(a) isC₁₋₃alkyl and Rb is methyl.
 6. The compound of claim 1 wherein W is agroup of formula (III).
 7. The compound of claim 6 wherein p is
 0. 8.The compound of of claim 6 wherein n is
 1. 9. The compound of claim 1wherein W is a group of formula (IV).
 10. The compound of claim 1wherein m is 1 and q is
 1. 11. The compound of claim 1 wherein: R¹ ishydrogen or halo; R² is C₃₋₄alkyl or C₄₋₅cycloalkyl; and W is selectedfrom the group consisting of: (i) a group of formula (II) wherein X isNC(O)CH₃, S(O)₂, or NS(O)₂CH₃; (ii) a group of formula (III) wherein pis 0, n is 1, and Y is NCH₃C(O)CH₃; and (iii) a group of formula (IV)wherein R^(z) is methyl, m is 1, q is 1, and Z is NC(O)CH₃, S(O)₂, orNS(O)₂CH₃.
 12. The compound of claim 11 wherein W is a group of formula(II) wherein X is NC(O)CH₃, S(O)₂, or NS(O)₂CH₃.
 13. The compound ofclaim 1 wherein the compound is selected from:1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)-ethyl]8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-(tetrahydrofuran-2-carbonyl)piperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(1,1-dioxo-1λ⁶thiomorpholin-4-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-methanesulfonylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-cyclohexylmethanesulfonylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-methanesulfonylmethanesulfonylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(3-(acetyl-methylamino)pyrrolidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(3-(acetyl-amino)pyrrolidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-((R)-3-(acetyl-amino)pyrrolidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-((S)-3-(acetyl-amino)pyrrolidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[3-((S)-2-hydroxypropionylamino)pyrrolidin-1-yl]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[(3S,4S)-3-(acetylmethylamino)-4-hydroxypyrrolidin-1-yl]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-((R)-3-ethanesulfonylaminopyrrolidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-((R)-3-cyclohexylmethanesulfonylaminopyrrolidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[3-(acetyl-methylamino)piperidin-1-yl]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(3-acetylaminopiperidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(3-methanesulfonylaminopiperidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-((S)-3-methanesulfonylaminopiperidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-((S)-3-ethanesulfonylaminopiperidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-((S)-3-methanesulfonylmethanesulfonylaminopiperidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[(1-acetylpyrrolidin-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[((R)-1-acetylpyrrolidin-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[((S)-1-acetylpyrrolidin-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[(1-methanesulfonylpyrrolidin-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[((R)-1-methanesulfonylpyrrolidin-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[(1,1-dioxo-tetrahydro-1λ⁶-thiophen-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[(1,1-dioxotetrahydro-1λ⁶-thiophen-3-yl)-(2-hydroxyethyl)amino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[(1-acetylpiperidin-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[(1,1-dioxo-hexahydro-1λ⁶-thiopyran-4-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[(1-methanesulfonylpiperidin-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;5-fluoro-1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-propyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-butyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-cyclobutyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-cyclopentyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-((R)-3-(acetylmethylamino)pyrrolidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-((S)-3-(acetylmethylamino)pyrrolidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[((S)-1-methanesulfonylpyrrolidin-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[(R)-(1,1-dioxo-tetrahydro-1λ⁶-thiophen-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[(S)-(1,1-dioxotetrahydro-1λ⁶-thiophen-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;and pharmaceutically-acceptable salts and solvates and stereoisomersthereof.
 14. The compound of claim 1 wherein the compound is selectedfrom: 1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)-ethyl]8-azabicyclo[3.2.1]oct-3-yl}amide; 1-isopropyl-1H-indazole-3-carboxylicacid {(1S,3R,5R)-8-[2-(1,1-dioxo-1λ⁶thiomorpholin-4-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-methanesulfonyl-piperazin-1-yl)-ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(3-(acetylmethyl-amino)pyrrolidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-((R)-3-(acetyl-methyl-amino)pyrrolidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-((S)-3-(acetylmethylamino)pyrrolidin-1-yl)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-[(1-acetylpyrrolidin-3-yl)methylamino]ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-[((R)-1-acetylpyrrolidin-3-yl)methylamino]ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-[((S)-1-acetyl-pyrrolidin-3-yl)methylamino]ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide; 1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[(1-methanesulfonyl-pyrrolidin-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[((R)-1-methanesulfonyl-pyrrolidin-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;1-isopropyl-1H-indazole-3-carboxylic acid((1S,3R,5R)-8-{2-[((S)-1-methanesulfonyl-pyrrolidin-3-yl)methylamino]ethyl}-8-azabicyclo[3.2.1]oct-3-yl)amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-((1,1-dioxo-tetrahydro-1λ⁶-thiophen-3-yl)methylamino)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}-amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-((R)-(1,1-dioxotetrahydro-1λ⁶-thiophen-3-yl)methylamino)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-((S)-(1,1-dioxo-tetrahydro-1λ⁶-thiophen-3-yl)methylamino)ethyl]-8-azabicyclo[3.2.1]oct-3-yl}amide;and pharmaceutically-acceptable salts and solvates and stereoisomersthereof.
 15. A compound having the chemical name1-isopropyl-1H-indazole-3-carboxylic acid{(1S,3R,5R)-8-[2-(4-acetylpiperazin-1-yl)ethyl]-8-aza-bicyclo[3.2.1]oct-3-yl}amide;or a pharmaceutically-acceptable salt or solvate thereof.
 16. Apharmaceutical composition comprising a therapeutically effective amountof the compound of claim 1 or claim 15 and a pharmaceutically acceptablecarrier.
 17. A method of treating a mammal having a medical conditionassociated with 5-HT₄ receptor activity, the method comprisingadministering to the mammal, a therapeutically effective amount of apharmaceutical composition comprising a pharmaceutically-acceptablecarrier and a compound of claim 1 or claim
 15. 18. A method of treatinga disorder of reduced motility of the gastrointestinal tract in amammal, the method comprising administering to the mammal, atherapeutically effective amount of a pharmaceutical compositioncomprising a pharmaceutically-acceptable carrier and a compound of claim1 or claim
 15. 19. The method of claim 18, wherein the disorder ofreduced motility is selected from chronic constipation,constipation-predominant irritable bowel syndrome, diabetic andidiopathic gastroparesis, and functional dyspepsia.
 20. A process forpreparing a compound of claim 1, the process comprising reacting acompound of formula 5:

or a salt or stereoisomer or protected derivative thereof with an amineof formula H—W in the presence of a reducing agent to provide a compoundof formula (1) or a pharmaceutically-acceptable salt or solvate orstereoisomer thereof.
 21. The product prepared by the process of claim20.
 22. A compound of formula 5:

wherein R¹ is hydrogen, halo, hydroxy, C₁₋₄alkyl, or C₁₋₄alkoxy, and R²is C₃₋₄alkyl, or C₃₋₆cycloalkyl; or a salt or stereoisomer or protectedderivative thereof.
 23. A process for preparing a compound of claim 1,the process comprising reacting a compound of formula 2:

with a compound of formula 10:

under amide coupling conditions to provide a compound of formula (I) ora pharmaceutically-acceptable salt or solvate or stereoisomer thereof.24. A process for preparing(1S,3R,5R)-3-amino-8-azabicyclo[3.2.1]octane-8-carboxylic acidtert-butyl ester, the process comprising reacting3-oxo-8-azabicyclo[3.2.1]octane-8-carboxylic acid tert-butyl ester withat least 25 equivalents of ammonium formate in the presence of atransition metal catalyst to provide(1S,3R,5R)-3-amino-8-azabicyclo[3.2.1]octane-8-carboxylic acidtert-butyl ester.
 25. A method of studying a biological system or samplecomprising a 5-HT₄ receptor, the method comprising: (a) contacting thebiological system or sample with a compound of claim 1 or claim 15; and(b) determining the effect caused by the compound on the biologicalsystem or sample.